Acute Angle Degree


Constructing a 90º Angle. Look back at Figure 1. Find the angle measure. These are like the edges of a wooden block. Angles having magnitudes 30°, 40°, 60° are all acute angles. Homework Statement Help !! How can I find acute Angle theta?? How to find acute angle theta ,when tan 63 Degree = cot theta??Could anyone help me to find answer of this query. And then, if you get all the way to 180 degrees, your angle actually forms a line. The number 360 has 24 divisors, making it a fairly easy number to work with. For example, even if the angle was the minimum 1 degree, the complement is still 89 degrees, which is. The main theorem cos (−θ) and sin (−θ) Polar coördinates Proof of the main theorem H OW SHALL WE EVALUATE tan 118°, for example? We will see that we will be referred back to an acute angle. com N T Q O U R P V S Use a protractor to measure Also, tell whether the angle is acute, obtuse, or right. For the vectors shown below, determine the values of A and the acute angle 2 (in degrees) that would make v1+Av2=−5i−7j. For example, an acute triangle could have an 80-degree angle, a 55-degree angle and a 45-degree angle. After completing a 360 degree laser, the IOP decreased to 8 mm Hg and then stabilized around 12 mm Hg. To recall, an acute angle is an angle that is less than 90°. Yes, because the measures add up to 180 o. If an angle is in degrees, it is only acute if it is between 90 and 0, exclusive. Acute angles; Obtuse angles; Right angles Right angles are angles that have a measure of exactly 90°. How many can you find? Right angles have 90 degrees. 90 degrees is neither an acute angle nor an obtuse angle, it is what is called a right angle. Additional Information In most cases, only a single entry is needed. 017455 which means that when an object's size is. An angle that is exactly 180 degrees is called a straight angle (this appears as a straight line). Example sentences with the word angle. Since a triangle's angles must sum to 180° in Euclidean geometry, no Euclidean triangle can have more than one obtuse angle. Right angles are the most common feature found in most sheet metal. co-terminal angles Angles of rotation in standard position are co-terminal of they share the same terminal side. For example, even if the angle was the minimum 1 degree, the complement is still 89 degrees, which is. The welded edge of the shear plate would be prepped to give us a 45 degree weld groove. For example, the angle at the corner of a square or rectangle is a right angle. An acute angle triangle (or acute angled triangle) is a triangle that has acute angles as all of its interior angles. For acute angles to be congruent, they have to have the same angles measurement. Acute Angle Definition Acute Angle Definition Acute angle is one of the types of angles whose measure is below 90 degree and above 0 degree. It may be defined as the acute angle between two lines normal to the planes. protractor. Acute Angle Cloud (AAC) is a cryptocurrency token and operates on the Ethereum platform. To take all these wonderful obtuse angles that we used to have -- these huge big boards with great broad representation -- and bring it together in some way,” said DeVries. Actually, it’s just a pinch. It's as easy as entering the value of the angle in degrees and the calculator will determine the reference angle. ” @Hollyj_1310 We made this up in geometry! 1 reply 1 retweet 1 like. An acute angle measures between 0 and 90 degrees, a right angle measures 90 degrees, and an obtuse angle is between 90 and 180 degrees. Angle x is three times the size of y and 1/2 the size of z. An obtuse angle is greater than 90 degrees but less than 180 degrees. Double-click on the angle symbol, click the “Select” button, then click the “Copy” button. Type of Angle Description; Acute Angle: is less than 90° Right Angle: is 90° exactly: Obtuse Angle: is greater than 90° but less than 180° Straight Angle: is 180° exactly: Reflex Angle: is greater than 180° Full Rotation: is 360° exactly. How do I use these obtuse acute and right angles worksheets? These worksheets deal with acute, obtuse and right angles. Important Facts About Measuring Angles: An angle is measured in units called degrees. 24 % over the last 24 hours. Smaller degrees of peak DF during gait were observed during brace conditions that imposed larger restrictions on DF. But perhaps something is hindering your ability to cut--leaving the saw's gauge with a limited. Two angles are said to be complementary if their sum equals 90º. In the zero case the axis does not matter and can be anything because there is no rotation round it. obtuse angle An obtuse angle is an angle with measure between 90 and 180 degrees. 1 Converting Between Degrees and Radians. An acute angle is one whose measure is less than 90 degrees. Acute Angle. Loading Unsubscribe from mathantics? How to measure angles using a protractor - why does it have two sets of measurements?. So, in a right triangle, it should be noted that the two acute angles are complementary. A right triangle is any triangle with a right, or 90-degree, angle. Loading Unsubscribe from mathantics? How to measure angles using a protractor - why does it have two sets of measurements?. Sometimes, other medications or even glaucoma filtration surgery may be needed to ultimately control the eye pressure. Galvanised 45 degree acute angle "T" bracket suitable for our Brundstrut channel support system. Affordable and search from millions of royalty free images, photos and vectors. Angle 3 and Angle C fields are NOT user modifiable. It is not possible for a triangle to have more than one vertex with internal angle greater than or equal to 90°, or it would no longer be a triangle. Acute Angled Triangle: When all the angles of a triangle are less than 90 degrees, then the triangle is called an acute triangle. angle of jaw the junction of the lower edge with the posterior edge of the lower jaw. Using acute, obtuse, reflex and right angles. For the vectors shown below, determine the values of A and the acute angle 2 (in degrees) that would make v1+Av2=−5i−7j. filtration angle (angle of the iris) the angle between the iris and cornea at the periphery of the anterior chamber of the eye, through which the aqueous humor readily permeates. This is an acute angle. An acute triangle has angles that are all less than 90 degrees. two angles are supplementary and their difference is 24. For example, mark at 90 for a 90 degree angle Use the straight edge of the protractor to connect the mark to the end point of the first line, forming an angle. An example of a right angle is below: Straight angles Right angles are angles that have a measure of exactly 180°. ∠ABC measures 30 ̊and hence it is an acute angle A triangle formed by all angles measuring less than 90˚ is also known as an acute triangle. For many practical purposes, a degree is a small enough angle that whole degrees provide sufficient precision. Depending on the math level you’re at and the particular angle you’re dealing with, you can calculate angle degrees with a few different methods. Again, this right triangle calculator works when you fill in 2 fields in the triangle angles, or the triangle sides. Click on one of them to start using it. Right Angle. It's any angle that measures more than 0 degrees but less than 90 degrees. Angles Greater than 360 Degrees Date: 01/01/99 at 09:41:21 From: Queenie Subject: Angles -- Reflex, obtuse or acute? Hi Dr. ∠ABC measures 30 ̊and hence it is an acute angle A triangle formed by all angles measuring less than 90˚ is also known as an acute triangle. 0 degree angle. In this section, we will consider the use of a protractor. 58 o, acute. The general form of an acute angle is 0 < theta < 90. Learn about angles with this interactive angle game for kids. Each angle is thesupplement of the other. Definition of acute in the Definitions. For example, an acute triangle could have an 80-degree angle, a 55-degree angle and a 45-degree angle. Degrees are indicated by the ° symbol, so 35° means 35 degrees. acute-angle | definition: an angle less than 90 degrees but more than 0 degrees | synonyms: oblique angle| antonyms: right angle Synonym. acute angle definition: The definition of an acute angle is one that is less than 90 degrees. 1 question of 5. Angles having magnitudes 30°, 40°, 60° are all acute angles. Define the straight as an angle which is equal with 180 degree or ½ turn. Trigonometry primarily concerns itself with measurements and ratios of this special type of. One thing complementary angles always do is add up to 90 degrees. 0 degree angle. All you have to do is simply input any positive angle into the field and this calculator will find the reference angle for you. because if you put them all together they form the angle all the way round a point:. The angle between the positive x axis and this line is θ = tan^(-1)(4/5) = 38. A right triangle is any triangle with a right, or 90-degree, angle. Alternate Exterior Angles - When two parallel lines are cut by a transversal, the two angles on opposite sides of the transversal and outside the parallel lines (an example below). An acute angle triangle (or acute angled triangle) is a triangle that has acute angles as all of its interior angles. acute angle synonyms, acute angle pronunciation, acute angle translation, English dictionary definition of acute angle. An anteriorly rotated or abnormally oversized ciliary body occludes the ciliary sulcus, blocking access to the trabecular meshwork and resulting in elevated intraocular pressure. How many can you find? Right angles have 90 degrees. The reference angle is the positive acute angle that can represent an angle of any measure. Angles can also be measured in other units like radians. They are measured in degrees, written with the degree sign °. acute angle An acute angle is an angle with measure between 0 and 90 degrees. For additional information or to place an order by phone please contact customer service at 800-400-4484 ext. What does acute angle mean? Proper usage and audio pronunciation (plus IPA phonetic transcription) of the word acute angle. Right Triangle Trigonometry - SohCahToa Answer (round to nearest degree): X =. Again, this right triangle calculator works when you fill in 2 fields in the triangle angles, or the triangle sides. Constructing a 90º Angle. Differentiated sheets used to help children identify right, acute and obtuse angles. An acute angle is less than 90 degrees. A full circle has 360°. The corresponding acute angle. You can change their names, and they are sorted by use. The final type of angle hides in plain sight – it’s sorta the chameleon of the angle. The three interior angles in a triangle always add up to 180 degrees. Find the angle measure. So in Degrees mode, my calculator solves this as C = 33. Put the centre of your protractor on the point of the angle. An angle is formed when two lines meet at a shared point. An angle that has measure less than 90°. The angles are less than 1 turn and larger than a straight angle. Definition of acute angle in the Definitions. If the angle expands to the 2 nd quadrant, you would use the expression 180-the angle° = the reference angle. Wide-Angle Miter Saw Jig A miter saw is a handy tool around the shop for a number of jobs. If you’re a WOMAN, read this… As a woman, deep down you want to find “the one” that can fulfill all your personal needs. The exterior angles of a shape are the angles you get if you extend the sides. We can construct a 90º angle either by bisecting a straight angle or using the following steps. thats gives the angle between digit 11 and hour hand when the time is 11:50. Unit Descriptions; 1 Hour Angle: 1 Hour angle is 1 turn/24 or 15°. An acute triangle, therefore, is a triangle whose three angles each measure less than 90 degrees. First I rewrite the law of cosines in terms of angle B: b 2 = a 2 + c 2 - 2ac cos(B). Alternate interior angles have the same degree measurement. Acute really means "sharp" or "severe" or "intense" and modifies certain kinds of angles in geometry or describes a certain kind of illness of short duration. An acute angle is an angle whose measure is between 0 and 90 degrees. Rock, Paper, Scissors Math Game to Teach Angles: The purpose of this Instructable is to help students distinguish between Acute, Obtuse, Right & Straight Angles by playing a variation of Rock, Paper & Scissors. for a reflex angle it is the angle greater than 180 degrees as opposed to the obtuse (or acute) angle that would be measured from the 'other side'. 1, 6 If A and B are acute angles such that cos A = cos B, then show that A = B. One thing complementary angles always do is add up to 90 degrees. Practice classifying angles as acute, right, obtuse, or straight by playing this interactive game. The standard unit of measuring an angle is degree. Angle of degree 1. The two sides which form the 90º angle are called the legs of the right triangle. The inches box will also accept decimal values making it possible to calculate the degrees for any slope! For a quick reference for getting the angle of a pitch, use a speed square. cos A = (Side adjacent of angle A) / Hypotenuse = AC/AB Similarly, cos B = (Side adjacent of angle A) / Hypotenuse = BC/AB Now it is given that cos A = cos B AC/AB = BC/AB AC = BC We know that in a triangle, angles opposite equal sides are equal B = A Hence proved. Use a calculator to approximate the measure of angle A to the nearest tenth of a degree. Get facts about algebra here. You can see from the definition of reflex angles that you do need to be aware of which angle it is that we are interested in, i. An acute angle is an angle that measures less than 90 degrees. com Skip to main content. Answer to Find the acute angle between the lines. Lie a zero line of the protractor over one side of the angle. A right triangle is a three sided figure with one angle equal to 90 degrees. Angle Degrees 1. The rev is a unit of angular measure which is equal to one 'revolution' or 360 degrees. An angle that has a measure greater than 90 degrees and less than 180 degrees is called a(n) angle. I arbitrarily chose 12″ x 12″ for this jig. • A right angle has an exact measurement of 90 degrees. Math Antics - Angles & Degrees mathantics. Line up one side of the angle with the zero line of the protractor (line with the number 0). net dictionary. Acute Angles are angles with a measure between zero and ninety degrees. oblique angle definition: The definition of an oblique angle is one that is not 90 degrees. Keep playing until the problems seem easy and you can solve them quickly. Then have them determine if the angle is less than or greater than 45 degrees. Trigonometry primarily concerns itself with measurements and ratios of this special type of. (If graphing or working with radians isn't your thing, you could also check that it is between 270 and 360 degrees. Darren is a hero for Northern Ireland everyman. ) Sine of an angle equals the y-coordinate on the unit circle. For equilateral triangles, which are a specific type of acute triangles whose angles all have the same measurements, consists of three 60 degree angles and equal length segments on each side of the figure, but for all triangles, the internal measurements of the angles always add up to 180 degrees, so if one angle's measurement is known, it's typically relatively simple to discover the other. Simply line up the common slope with any straight edge and see what degree it is on. The smaller angle is an Acute Angle, but the larger angle is a Reflex Angle Types of Angles Right Angles Obtuse Angles Straight Angle Reflex Angles Angles On a Straight Line Angles Around a Point Degrees (Angle) Geometry Index. But you could have 1, 2, 3, 4 or 5 acute angles. Switch the hypothesis and conclusion of the orginal statement. An angle can also be thought of as a fraction of a circle. Looking for GRAINGER APPROVED Steel Channel Angle Bracket, 45° Acute, Galv-Krom Finish (2HAE6)? Grainger's got your back. The 30-60-90 right triangle is a special case triangle, with angles measuring 30, 60, and 90 degrees. For any pair of parallel lines 1 and 2, that are both intersected by a third line, such as line 3 in the diagram below, angle A and angle D are called alternate interior angles. So, -145+360=215 degrees. An angle consists of two different rays with the same endpoint. Independent Practice. Two angles are complementary angles if the sum of their measures is 908. So in Degrees mode, my calculator solves this as C = 33. 1 question of 5. We can construct a 90º angle either by bisecting a straight angle or using the following steps. Since a triangle's angles must sum to 180° in Euclidean geometry , no Euclidean triangle can have more than one obtuse angle. Is it acute, obtuse or a right angle? 1. √ 3 to be approximately 1. Triangle facts, theorems, and laws. The definition of an acute angle as "one less then 90 degrees" is for unsigned angles. An angle that has measure less than 90°. 017455 times its distance, it has an angular size of 1 degree. An angle of less than 90°. 4x − y = 2, 3x + y = 6 Was stuck on this and didn't understand how they were able to use the vectors a = <1, 4> and b =<1,-3>. Acute angle-closure glaucoma (AACG) is an ocular emergency and receives distinction due to its acute presentation, need for immediate treatment, and well-established anatomic pathology. Constructing a 90º Angle. So why does the die angle change? There are two separate but overlapping answers; one relates to narrow die openings, and the other pertains to larger dies. Use a protractor to measure. Complementary Angles Two angles are complementary if the sum of their measures is equal to 90 degree. Angle C is always 90 degrees; angle 3 is either angle B or angle A, whichever is NOT entered. Because if this angle was able to be exactly 90 degrees it would be a right angle if it was less than 90 it would be acute. Points are scored on the difference of the estimate and the actual size of each angle. 105º Obtuse 2. For the complementary angle, reverse the rise and run. 22 Degree Obtuse Angle Bracket. When a chord is a diameter, the central angles measures two,two,three,four right angles and the corresponding inscribed angles are all right,acute,right,obtuse. Acute Angle: An angle whose measure is more than 0° but less than 90° is called an acute angle. Functions of Acute Angles The characteristics of similar triangles , originally formulated by Euclid, are the building blocks of trigonometry. The acute angle is 20 degrees. A right triangle has one right angle and two acute angles. The angles are less than 1 turn and larger than a straight angle. Converse:If angle A is an acute angle,then meausre angle A equals 30 degrees. n an angle less than 90 degrees but more than 0 degrees. An acute angle is any angle smaller than a right angle. Acute Angle Cloud has a current supply of 1,000,000,000 AAC with 250,000,000 AAC in circulation. Develop protractor usage skills. An acute triangle is a triangle where all the interior angles are less than 90 degrees. An angle is a shape, formed by two lines diverging from a common point. Round your answer to the nearest degree. FAQ & Help page. Have students select an acute angle from the first triangle, and show them that they can visualize whether the angle is less than or greater than 90 degrees. The term 'open-angle' refers to the angle formed in the eye between the outer edge of the iris and sclera. Comparision of Angles. The rule where all designers would agree is: avoid any angle other than 45 o 90 degrees. A way to remember Sometimes we can confuse acute and obtuse angles. (noun) An example of an oblique angle is one that is 95 degrees. You can change their names, and they are sorted by use. For example, mark at 90 for a 90 degree angle Use the straight edge of the protractor to connect the mark to the end point of the first line, forming an angle. A right angle is an angle whose measure is exactly 90°. Angle Degrees 1. For acute angles to be congruent, they have to have the same angles measurement. An angle measures 91 degrees. 60, 60 and 60 degrees can make up a triangle 2 acute angles and a right angle, say 45 and 45 degrees and 90 degrees make a triangle any obtuse angle + a right angle will be larger than 180 degrees, so no triangle can exist. Improve your math knowledge with free questions in "Acute, obtuse, and right triangles" and thousands of other math skills. The problem would be even stronger for acute angles, which are strongly discouraged. Remember to look carefully at which angle you are being asked to name: The acute angle is the small angle which is less than 90°. 9 x = -82. In air forming, the bend angle does not depend exclusively on the angle of the die. Improve your math knowledge with free questions in "Acute, right, obtuse, and straight angles" and thousands of other math skills. acute angle definition: The definition of an acute angle is one that is less than 90 degrees. ASCII code Angle quotes, guillemets, right-pointing quotation mark, American Standard Code for Information Interchange, ASCII table, characters, letters, vowels. Right triangle trigonometry relates the sides of a right triangle to the angle measures of the two acute angles. Angle B and angle C are also alternate interior angles. An angle is called an obtuse angle if its magnitude is in between π/2 rad or 90° and π rad or 180°. Examples of how to use "acute angle" in a sentence from the Cambridge Dictionary Labs. The three interior angles in a triangle always add up to 180 degrees. To simply convert from any unit into degrees, for example, from 5 radians, just multiply by the value in the right column in the table below. ACUTE ANGLE SQUARES 45 degree DIN875/11 Flat, carbon steel with back, carbon steel. The standard unit of measuring an angle is degree. All acute angles have a complement, and collectively they add up to 90 degrees. When zero is reached, the angle given by the function ticks back over to -90 degrees again. Complementary Angles Two angles are complementary if the sum of their measures is equal to 90 degree. When a single angle is drawn on a xy-plane for analysis, we'll draw it in standard position with the vertex at the origin (0,0), one side of the angle along the x-axis, and the other side above the x-axis. 01) Post-hoc tests revealed that ankle DF angle was significantly different between each braced condition (p < 0. And in the second quadrant, sin θ is positive. Acute Angle Definition Acute Angle Definition Acute angle is one of the types of angles whose measure is below 90 degree and above 0 degree. General (17 matching dictionaries) acute angle: American Heritage Dictionary of the English Language [home, info] acute angle: Collins English Dictionary [home, info] acute angle: Vocabulary. Free trial available at. thats gives the angle between digit 11 and hour hand when the time is 11:50. Larger than 90 degrees, you have an obtuse angle. To learn about trigonometric functions of an acute angle Consider a right triangle ABC , with the right angle at C and with lengths a , b , and c , as in the figure on the right. The definition of an acute angle as "one less then 90 degrees" is for unsigned angles. Example sentences with the word angle. We classify angles into three types as follows: If an angle A has measure , then is said to be acute. Acute Angle unknown. Synonyms for acute angle in Free Thesaurus. com [home, info] acute angle: Macmillan Dictionary [home. Usually, when a finer measure is needed we just add decimal places to the degrees. The angle is 300 degrees, so it checks out that way as well. If you choose the larger angle you. find the angles. Leg Acute Angle Theorem - Example. This will help them narrow the angle's range to 45 degrees (0-45 or 45-90). Click on the first link on a line below to go directly to a page where "acute angle" is defined. Complementary angles form a right angle (L shape) and have a sum of 90 degrees. A way to remember Sometimes we can confuse acute and obtuse angles. In order to do this, a great pick-up line can help break the ice, but next you need to understand what it really takes to get a guy to love you, and how to keep him interested in you. In geometry, an angle. In this unit students learn to identify and construct right, acute and obtuse angles, and they begin to appreciate the degree as the unit of measurement of angle. If m angle A equals 30 degrees, then angle A is an acute angle. If pressed, I think I would define an acute angle as one that is between -90 and 90 degrees, so 0 would be acute. These worksheets require students to look at an angle and identify whether it is right, acute or obtuse. At 90 degrees, you have a right angle. I cut a 12″ x 12″ piece of 3/4″ plywood and then cut it diagonally to make a brace for this jig. An acute triangle, therefore, is a triangle whose three angles each measure less than 90 degrees. Online protractor or angle problems with acute, obtuse, reflex angles. Meaning of acute angle. 01) Post-hoc tests revealed that ankle DF angle was significantly different between each braced condition (p < 0. In an obtuse triangle, one of the angles of the triangle is greater than 90°, while in an acute triangle, all of the angles are less than 90°, as shown below. Angles can also be measured in other units like radians. A degree is a measure of angle equal to 1/360th of a revolution, or circle. A right angle forms part of a square, which is why it's often depicted by a square at. This will help them narrow the angle's range to 45 degrees (0-45 or 45-90). 8x − y = 5, 4x + y = 8. When two arms of an angle lie on each other, 0° angle is formed. Simple element illustration from Other concept. All cuts on a straight board leave 2 angles as measured with a protractor. When two arms of an angle lie on each other, 0° angle is formed. " Good Hunting! RD. Angle 3 and Angle C fields are NOT user modifiable. Define acute angle. There are many types of angles depending on the size or magnitude of an angle. Converse:If angle A is an acute angle,then meausre angle A equals 30 degrees. The range of an acute angle is between 0 and 90 degrees. You can call it acute angle if the angles are smaller than a right angle. Measuring angles is pretty simple: the size of an angle is based on how wide the angle is open. A right triangle is any triangle with a right, or 90-degree, angle. Obtuse Angle is greater than a right angle and is between 90-180 degrees. The reference angle is the positive acute angle that can represent an angle of any measure. Example: Consider ΔABC in the figure below. \$\begingroup\$ All other things being equal, 90 degrees is better than the acute angle! \$\endgroup\$ – Dave Tweed ♦ Mar 14 '14 at 15:42 4 \$\begingroup\$ @noufal, the reason to avoid right angles is to avoid excess capacitance in the trace, and it applies only to high-speed signals (say 100 MHz or higher). Additional Information In most cases, only a single entry is needed. How to Label Angles. 22 Degree Obtuse Angle Bracket. How do I use these obtuse acute and right angles worksheets? These worksheets deal with acute, obtuse and right angles. This picture shows a pumpkin pie from the food industry with two congruent acute angles. If an angle is in degrees, it is only acute if it is between 90 and 0, exclusive. An angle is acute if its magnitude is less than π/2 rad or 90° (i. I searched the net and found this simple. Acute angles are the smallest, being between (but not including) zero and 90° Note also that acute triangles are those where all the interior angles are acute. In the zero case the axis does not matter and can be anything because there is no rotation round it. Yes, because the measures add up to 180 o. Click on the first link on a line below to go directly to a page where "acute angle" is defined. Finding the third angle of a triangle when you know the measurements of the other two angles is easy. I am looking more for information on the pitfalls of such a design. It specifies an angle created by a rotation of approximately 3. An acute angle is the one that is greater than 0° and less than 90°. Angles are important to defining and studying polygons such as triangles and quadrilaterals. Acute Square Triangulation. Here is an example of an acute angle: We also learned about obtuse angles. obtuse angle An obtuse angle is an angle with measure between 90 and 180 degrees. This angle estimation game from nrich is brilliant ; Plenary. Acute angles can be found all around us. Example sentences with the word angle. An obtuse angle is defined as an angle that is between 90° and 180° in measure. What are Complementary Angles? Do complementary angles always have something nice to say? Maybe. The number of significant values entered will determine the number of significant figures in the results. Our reference angle calculator is a handy tool for recalculating angles into their acute version. Practice classifying angles as acute, right, obtuse, or straight by playing this interactive game. 90 degrees is neither an acute angle nor an obtuse angle, it is what is called a right angle. A right triangle is any triangle with a right, or 90-degree, angle. So, -145+360=215 degrees. The normal picture of the acute angle is given as, Pictures of acute angle: The acute angles are referred by using the pictures which measures the. So you would add 35 and 40 together which is 75. • measure of an angle. An acute angle is an angle that measures less than 90 degrees. A unit of angle measure equal to of a complete revolution. the perimeter of a rectangle is 64 cm.