Angle Relationships & Triangle Sum Theorems

Front

What is the Triangle Sum Theorem?

Back

The Triangle Sum Theorem states that the sum of the interior angles of a triangle is always 180 degrees.

Front

If angle A and angle B are complementary, what is the relationship between them?

Back

If angle A and angle B are complementary, then their measures add up to 90 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 measure of each angle in an equilateral triangle?

Back

In an equilateral triangle, each angle measures 60 degrees.

Front

If two angles are supplementary, what is their sum?

Back

If two angles are supplementary, their sum is 180 degrees.

Front

What is an acute angle?

Back

An acute angle is an angle that measures less than 90 degrees.

Front

What is an obtuse angle?

Back

An obtuse angle is an angle that measures more than 90 degrees but less than 180 degrees.

Front

How do you find the measure of a missing angle in a triangle?

Back

To find the measure of a missing angle in a triangle, subtract the sum of the known angles from 180 degrees.

Front

What is the relationship between the angles in a right triangle?

Back

In a right triangle, one angle is 90 degrees, and the sum of the other two angles is 90 degrees.

Front

If angle C is 40 degrees, what is the measure of its complement?

Back

The complement of angle C is 50 degrees (90 - 40 = 50).