# What is an angle measure?

Table of Contents

## What is an angle measure?

An angle is a measure of the size of the opening of two lines that intersect. The VERTEX is the point of intersection, while the lines that form the opening are called the SIDES. The angles are measured in degrees. A Right Angle is 90 degrees or 1/4 of a circle.

### How do you find the measure of an angle with only one angle?

Use the sine rule if given only one angle and two lengths of a triangle. The formula is sin A/a = sin B/b, where “A” and “B” are angles and “a” and “b” are the lengths of the sides opposite these angles, respectively.

**What is the measure of angle one?**

45°

Angle 1 and angle 2 are complementary and congruent. The measure of angle 1 is 45°.

**How do you find an angle with two angles?**

We must use The Law of Cosines first to find any one of the three angles, then we can use The Law of Sines (or use The Law of Cosines again) to find a second angle, and finally Angles of a Triangle to find the third angle.

## How do you find the radian measure of an angle?

An alternate definition of radians is sometimes given as a ratio. Instead of taking the unit circle with center at the vertex of the angle θ, take any circle with center at the vertex of the angle. Then the radian measure of the angle is the ratio of the length of the subtended arc to the radius r of the circle.

### How to find the measure of an arc angle?

An arc angle’s measurement is shown as m ⌢ AB m A B ⌢ where A A and B B are the two points on the circle creating the arc. The m m means measurement, and the short curved line over the ⌢ AB A B ⌢ indicates we are referring to the arc.

**What is the best way to measure an angle?**

The best way to measure an angle is to use a protractor. To do this, you’ll start by lining up one ray along the 0-degree line on the protractor. Then, line up the vertex with the midpoint of the protractor.

**What is the measure of angle C in math?**

The equation to use is: angle A + angle B + angle C = 180-degrees. For example, say you have the following triangle. What is the measurement of angle C? Squares and rectangles have four right angles. If you add up the angles, you get 90 + 90 + 90 + 90 = 360. A quadrilateral also has four angles.