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Vertical angles review

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

Vertical angles

Vertical angles are angles opposite each other where two lines cross.
For example, angle, A, X, D and angle, B, X, C are vertical angles in the following diagram:
Want to learn more about vertical angles? Check out this video.

Practice set

Problem 1A
Are angle, A, P, D and angle, C, P, B vertical angles?
All segments that appear straight are straight.
Choose 1 answer:
Choose 1 answer:

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

Use vertical angles to find a missing angle measure

Let's look at an example.
What is the measure of angle x?
First, let's find the measure of the pink angle:
The pink and blue angles add up to 180, degrees because they are adjacent and form a straight line.
start color #ff00af, start text, p, i, n, k, space, a, n, g, l, e, end text, end color #ff00af, equals, 180, degrees, minus, start color #6495ed, 121, degrees, end color #6495ed, equals, start color #ff00af, 59, degrees, end color #ff00af
The pink and green angles also add up to 180, degrees because they are adjacent and form a straight line too.
start color #28ae7b, start text, g, r, e, e, n, space, a, n, g, l, e, end text, end color #28ae7b, equals, 180, degrees, minus, start color #ff00af, 59, degrees, end color #ff00af, equals, start color #28ae7b, 121, degrees, end color #28ae7b
The measure of angle x, equals, start color #28ae7b, 121, degrees, end color #28ae7b.

Practice

Problem 2A
What is the measure of angle x?
  • 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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