Angles in Triangles

Front

What is the sum of the angles in a triangle?

Back

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

Front

If two angles of a triangle are known, how can you find the third angle?

Back

Subtract the sum of the known angles from 180°.

Front

What is an acute angle?

Back

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

Front

What is a right angle?

Back

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

Front

What is an obtuse angle?

Back

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

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°.

Front

If one angle of a triangle is 90°, what type of triangle is it?

Back

It is a right triangle.

Front

What is the measure of the third angle if two angles are 65° and 25°?

Back

The third angle measures 90°.

Front

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

Back

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

Front

What is the measure of the missing angle if two angles are 70° and 40°?

Back

The missing angle measures 70°.