Angles and Equations

Front

What is an angle?

Back

An angle is formed by two rays (sides of the angle) that share a common endpoint (the vertex).

Front

What are complementary angles?

Back

Complementary angles are two angles whose measures add up to 90 degrees.

Front

What are supplementary angles?

Back

Supplementary angles are two angles whose measures add up to 180 degrees.

Front

What are vertical angles?

Back

Vertical angles are the angles opposite each other when two lines intersect. They are always equal.

Front

What is the sum of angles in a triangle?

Back

The sum of the interior angles in a triangle is always 180 degrees.

Front

How do you solve for an unknown angle in a right triangle?

Back

Use the fact that the sum of the angles in a triangle is 180 degrees, and one angle is 90 degrees.

Front

What is the equation for finding a complementary angle?

Back

If x is the measure of an angle, its complementary angle can be found using the equation: 90 - x.

Front

What is the equation for finding a supplementary angle?

Back

If x is the measure of an angle, its supplementary angle can be found using the equation: 180 - x.

Front

If two angles are supplementary and one angle measures 64°, what is the measure of the other angle?

Back

The other angle measures 116° (180 - 64 = 116).

Front

If two angles are vertical and one angle measures 66°, what is the measure of the other angle?

Back

The other angle also measures 66° because vertical angles are equal.