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Intros
Lessons
  1. Introduction to Supplementary, Complementary, Vertical, and Adjacent Angles
  2. What are supplementary angles?
  3. What are complementary angles?
  4. What are vertical angles?
  5. What are adjacent angles?
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Examples
Lessons
  1. Application of Supplementary Angles MATH7 17 1 1

    Find the value of xx.

    1. Complementary Angles on Polygons MATH7 17 1 2

      Which of the following pair(s) is/are complementary angles?

      1. ∠ABD\angle ABD and ∠ACD\angle ACD
      2. ∠ABC\angle ABC and ∠CBD\angle CBD
      3. ∠ACB\angle ACB and ∠CBD\angle CBD
    2. MATH7 17 1 3

      Which of the following pair(s) is/are complementary angles?

      1. ∠CDB\angle CDB and ∠ADB\angle ADB
      2. ∠ABD\angle ABD and ∠CBD\angle CBD
      3. ∠BCD\angle BCD and ∠BAD\angle BAD
    3. Application of Complementary Angles MATH7 17 1 4

      If ∠AOB=−9x+29\angle AOB=-9x+29 and ∠BOC=2x+82\angle BOC=2x+82, find the value of xx.

      1. Proving Vertical Angles Using Supplementary Angles

        Use the idea of supplementary angles to prove for vertical angles.

        1. Application of Vertical Angles MATH7 17 1 6

          Given that ∠m=\angle m=43°, find the remaining angles in the diagram.

          1. MATH7 17 1 7

            Given that ∠AOC\angle AOC=125° and ∠DOE\angle DOE=35°.

            1. Find ∠BOC.\angle BOC.
            2. Find ∠EOB.\angle EOB.
          2. MATH7 17 1 8

            If ∠AOD\angle AOD=3x+14 and ∠BOC\angle BOC=7x-18, find the value of x.

            1. Understanding Adjacent Angles

              What of the following is/are adjacent angles?

              1. MATH7 17 1 9a
              2. MATH7 17 1 9b
              3. MATH7 17 1 9c
              4. MATH7 17 1 9d
            2. Finding Adjacent Angles MATH7 17 1 10

              ∠AOB\angle AOB=30°, ∠AOC\angle AOC=100°.

              1. Are ∠AOB\angle AOB and ∠AOC\angle AOC adjacent?
              2. Find an angle that is adjacent to ∠AOB\angle AOB.
            Topic Notes
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            In this lesson, we will learn:
            • Application of Supplementary Angles
            • Complementary Angles on Polygons
            • Application of Complementary Angles
            • Proving Vertical Angles Using Supplementary Angles
            • Application of Vertical Angles
            • Understanding Adjacent Angles
            • Finding Adjacent Angles

            Notes:
            • Supplementary angles: two angles which add up to 180°, don't necessarily have to be together.
            • Complementary angles: two angles which add up to 90°, again, don't necessarily have to be together.
            • The "S" of Supplementary stands for "straight", and there are 180° on a straight line.
            • The "C" of Complementary stands for "corner", and there are 90° at a corner.
            • Vertical angles: angles opposite each other are the same when two lines cross
            • Adjacent angles: two angles sharing a common side and vertex, yet they do not overlap.