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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.
Want to learn more about complementary and supplementary angles? Check out this video.

Practice set 1: Identify complementary and supplementary angles

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

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

Practice set 2: Find a missing angle measure

Problem 2A
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.
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
  • an exact decimal, like 0, point, 75
  • a multiple of pi, like 12, space, start text, p, i, end text or 2, slash, 3, space, start text, p, i, end text
degrees

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

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