FLASHCARD 2: Angles in Triangles

Front

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

Back

The sum of the interior angles of a triangle is always 180 degrees.

Front

What is an acute angle?

Back

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

Front

What is a right angle?

Back

A right angle is an angle that measures exactly 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 one angle of a triangle is 60 degrees and another is 70 degrees, what is the measure of the third angle?

Back

The third angle measures 50 degrees, calculated as 180 - (60 + 70).

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.

Front

What is the exterior angle theorem?

Back

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

Front

If two angles are complementary, what is their sum?

Back

The sum of two complementary angles is 90 degrees.

Front

If two angles are supplementary, what is their sum?

Back

The sum of two supplementary angles is 180 degrees.

Front

What is the value of x if the angles in a triangle are x, 70 degrees, and 40 degrees?

Back

x = 70 degrees, calculated as 180 - (70 + 40).