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

Back

It is a right triangle.

Front

What do you call an angle that is less than 90°?

Back

An acute angle.

Front

What do you call an angle that is greater than 90° but less than 180°?

Back

An obtuse angle.

Front

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

Back

Subtract the sum of the known angles from 180°.

Front

If two angles in a triangle are 50° and 60°, what is the measure of the third angle?

Back

The third angle is 70°.

Front

Which of the following sets of angles can form a triangle: 30°, 60°, 90° or 30°, 60°, 120°?

Back

30°, 60°, 90° can form a triangle.

Front

What is the measure of the missing angle if the other two angles are 45° and 45°?

Back

The missing angle is 90°.

Front

What is an equilateral triangle?

Back

An equilateral triangle has all three angles equal to 60°.

Front

What is the relationship between the angles in a triangle and the sides?

Back

The largest angle is opposite the longest side.