Finding 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 degrees.

Front

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

Back

It is a right triangle.

Front

How do you find a missing angle in a triangle when you know the other two angles?

Back

Subtract the sum of the known angles from 180 degrees.

Front

What is an acute angle?

Back

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

Front

What is an obtuse angle?

Back

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

Front

If two angles in a triangle are 30 degrees and 70 degrees, what is the measure of the third angle?

Back

The third angle measures 80 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

What is the definition of a triangle?

Back

A triangle is a polygon with three edges and three vertices.

Front

If x + 30 + 70 = 180, what is the value of x?

Back

x = 80.

Front

What is the relationship between the angles in a right triangle?

Back

In a right triangle, one angle is 90 degrees, and the sum of the other two angles is 90 degrees.