Angles in a Triangle

Front

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

Back

180 degrees

Front

What is an "Acute" Angle?

Back

An angle that measures less than 90 degrees.

Front

What is an "Obtuse" Angle?

Back

An angle that measures more than 90 degrees but less than 180 degrees.

Front

What is a "Right" Angle?

Back

An angle that measures exactly 90 degrees.

Front

If one angle of a triangle is 90 degrees and another is 45 degrees, what is the measure of the third angle?

Back

45 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

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 formula to 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

If two angles in a triangle are equal, what type of triangle is it?

Back

It is an Isosceles triangle.

Front

What is a "Scalene" Triangle?

Back

A triangle with all sides of different lengths.