Angle relationships

Front

What is a supplementary angle?

Back

Two angles are supplementary if the sum of their measures is 180 degrees.

Front

If ∠A and ∠B are supplementary and ∠A measures 70 degrees, what is the measure of ∠B?

Back

∠B = 180 - 70 = 110 degrees.

Front

What is the relationship between complementary angles?

Back

Two angles are complementary if the sum of their measures is 90 degrees.

Front

If ∠C and ∠D are complementary and ∠C measures 30 degrees, what is the measure of ∠D?

Back

∠D = 90 - 30 = 60 degrees.

Front

What is an interior angle?

Back

An interior angle is an angle formed between two sides of a polygon that is inside the polygon.

Front

In a triangle, the sum of the interior angles is always equal to what?

Back

180 degrees.

Front

If one angle of a triangle measures 50 degrees and another measures 60 degrees, what is the measure of the third angle?

Back

Third angle = 180 - (50 + 60) = 70 degrees.

Front

What are vertical angles?

Back

Vertical angles are the angles opposite each other when two lines intersect. They are always equal.

Front

If two angles are vertical and one measures 45 degrees, what is the measure of the other angle?

Back

The other angle also measures 45 degrees.

Front

What is the definition of adjacent angles?

Back

Adjacent angles are two angles that share a common side and a common vertex.