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 is 90 degrees, what can you say about the other two angles?

Back

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

Front

What is the Exterior Angle Theorem?

Back

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

Front

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

Back

To find an unknown angle, subtract the sum of the known angles from 180 degrees.

Front

If angle A is 50 degrees and angle B is 60 degrees, what is angle C?

Back

Angle C = 180 - (50 + 60) = 70 degrees.

Front

What is the relationship between the angles in a triangle?

Back

The angles in a triangle are related such that their sum is always 180 degrees.

Front

If an exterior angle measures 120 degrees, what is the sum of the two remote interior angles?

Back

The sum of the two remote interior angles is 120 degrees.

Front

What is the measure of an angle if the other two angles in a triangle are 45 degrees and 85 degrees?

Back

The measure of the angle is 50 degrees.

Front

Can a triangle have two obtuse angles?

Back

No, a triangle cannot have two obtuse angles because the sum of the angles would exceed 180 degrees.

Front

What is an acute angle?

Back

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