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

What are corresponding angles?

Back

Corresponding angles are pairs of angles that are in similar positions at each intersection where a straight line crosses two others.

Front

If two angles are complementary, what is their sum?

Back

The sum of two complementary angles is 90 degrees.

Front

If two angles are supplementary, what is their sum?

Back

The sum of two supplementary angles is 180 degrees.

Front

What is the measure of each angle in an equilateral triangle?

Back

Each angle in an equilateral triangle measures 60 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 vertical angles?

Back

Vertical angles are equal; when two lines intersect, the opposite angles formed are congruent.

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

What is a right angle?

Back

A right angle is an angle that measures exactly 90 degrees.