Angles and Triangles

Front

What are complementary angles?

Back

Angles that add up to 90°.

Front

What are supplementary angles?

Back

Angles that add up to 180°.

Front

What are vertical angles?

Back

Angles that are opposite each other when two lines intersect; they are congruent.

Front

What are corresponding angles?

Back

Angles that are in the same position on different parallel lines cut by a transversal; they are congruent.

Front

What is the sum of angles in a triangle?

Back

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

Front

If one angle is 30°, what is the measure of its complementary angle?

Back

60°.

Front

If two angles are supplementary and one angle measures 120°, what is the measure of the other angle?

Back

60°.

Front

What is an acute angle?

Back

An angle that measures less than 90°.

Front

What is a right angle?

Back

An angle that measures exactly 90°.

Front

What is an obtuse angle?

Back

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