Angles and Angle Relationships

Front

What are complementary angles?

Back

Complementary angles are two angles whose measures add up to 90 degrees.

Front

What are supplementary angles?

Back

Supplementary angles are two angles whose measures add up to 180 degrees.

Front

What are vertical angles?

Back

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

Front

What are adjacent angles?

Back

Adjacent angles are two angles that share a common side and a common vertex but do not overlap.

Front

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

Back

60° (90° - 30° = 60°).

Front

If angle B measures 120°, what is the measure of its supplementary angle?

Back

60° (180° - 120° = 60°).

Front

What is the angle relationship between angles 1 and 2 if they add up to 90°?

Back

They are complementary angles.

Front

What is the angle relationship between angles 3 and 4 if they add up to 180°?

Back

They are supplementary angles.

Front

If two angles are vertical angles, what can we say about their measures?

Back

They are equal in measure.

Front

If angle C is 45° and angle D is adjacent to it, what is the measure of angle D if they are complementary?

Back

45° (90° - 45° = 45°).