An angle is created when two rays share a common endpoint, also called a vertex. Remember, a ray has one endpoint and goes on forever in one direction. Angles are also formed when lines or line segments intersect. Angles are measured in degrees. The measure of an angle comes from the degrees of a circle, which has 360 degrees.
You can think of the vertex of an angle as being the center point of a circle. The angle that the two rays form is a fraction of the circle’s circumference. For example, if the rays cover 1/360 of a circle, the angle measures 1 degree. You can find the measure of an angle by asking how many 1 degree angles it takes to make up that angle. For example, fifteen 1 degree angles would make a 15 degree angle.
How many 1 degree angles would make up a 90 degree angle?
A
1
B
15
C
45
D
90
B
15