Triangle Sum Theorem and Exterior Angle Theorem

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 one angle of a triangle measures 90 degrees, what can you say about the other two angles?

Back

The other two angles must sum to 90 degrees, making the triangle a right triangle.

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 the third angle in a triangle if you know the other two angles?

Back

Subtract the sum of the known angles from 180 degrees.

Front

What is the Exterior Angle Theorem?

Back

The Exterior Angle Theorem states that the measure of an exterior angle is equal to the sum of the measures of the two non-adjacent interior angles.

Front

If two angles of a triangle are 30 degrees and 70 degrees, what is the measure of the third angle?

Back

The third angle measures 80 degrees.

Front

What is the relationship between the angles in a triangle?

Back

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

Front

If one angle of a triangle is 75 degrees and the other is 45 degrees, what is the third angle?

Back

The third angle measures 60 degrees.

Front

What is the measure of an angle that is supplementary to a 120-degree angle?

Back

The supplementary angle measures 60 degrees.

Front

In a triangle, if one angle measures 79 degrees and another measures 43 degrees, what is the third angle?

Back

The third angle measures 58 degrees.