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# Complementary and supplementary angles review

Review the basics of complementary and supplementary angles, and try some practice problems.

## Complementary angles

Complementary angles are two angles with a sum of 90, degrees. A common case is when they form a right angle.

## Supplementary angles

Supplementary angles are two angles with a sum of 180, degrees. A common case is when they lie on the same side of a straight line.

## Practice set 1: Identify complementary and supplementary angles

Problem 1A
• Current
What is the relationship between angle, A, X, Y and angle, Y, X, B?
All segments that appear straight are straight.

Want to try more problems like this? Check out this exercise.

## Practice set 2: Find a missing angle measure

Problem 2A
• Current
If angle, A, O, C is a right angle and m, angle, A, O, B, equals, 79, degrees, what is m, angle, B, O, C?
Note: Angles not necessarily drawn to scale.
degrees

Want to try more problems like this? Check out this exercise.