Interior and Exterior Angles of Triangles

Front

What is an obtuse triangle?

Back

A triangle with one angle measuring more than 90 degrees.

Front

What is the sum of the interior angles of a triangle?

Back

180 degrees.

Front

What type of angle measures exactly 90 degrees?

Back

Right angle.

Front

If one angle of a triangle is 95 degrees, what type of triangle is it?

Back

Obtuse triangle.

Front

What is an acute triangle?

Back

A triangle where all angles are less than 90 degrees.

Front

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

Back

Subtract the sum of the known angles from 180 degrees.

Front

What is the exterior angle theorem?

Back

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 in a triangle are 45 degrees and 85 degrees, what is the measure of the third angle?

Back

50 degrees.

Front

What is a vertical angle?

Back

Angles that are opposite each other when two lines intersect; they are equal.

Front

What is the relationship between interior and exterior angles?

Back

Each exterior angle is equal to the sum of the two opposite interior angles.