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Write and solve equations: complementary angles

Year 8 maths · Fieldbook Learning

Name ______________________ Date __________

Write an equation that adds the two angles and sets it equal to the total, then solve for x.

  1. Two complementary angles measure (2x + 10)° and (4x + 14)°. Find x.
  2. Two complementary angles measure (2x + 9)° and (2x + 45)°. Find x.
  3. Two complementary angles measure (2x + 2)° and (x + 49)°. Find x.
  4. Two complementary angles measure (4x + 6)° and (4x − 36)°. Find x.
  5. Two complementary angles measure (x + 6)° and (x + 48)°. Find x.
  6. Two complementary angles measure (2x + 10)° and (2x + 32)°. Find x.
  7. Two complementary angles measure (3x + 5)° and (x + 41)°. Find x.
  8. Two complementary angles measure (4x)° and (x − 5)°. Find x.
  9. Two complementary angles measure (4x + 5)° and (3x + 15)°. Find x.
  10. Two complementary angles measure (3x + 5)° and (2x + 45)°. Find x.
  11. Two complementary angles measure (4x + 6)° and (4x − 12)°. Find x.
  12. Two complementary angles measure (3x + 3)° and (2x + 2)°. Find x.
  13. Two complementary angles measure (x + 3)° and (4x + 57)°. Find x.
  14. Two complementary angles measure (x + 8)° and (3x + 50)°. Find x.
  15. Two complementary angles measure (x + 2)° and (3x + 48)°. Find x.
  16. Two complementary angles measure (3x + 4)° and (2x + 11)°. Find x.
  17. Two complementary angles measure (3x + 9)° and (x − 15)°. Find x.
  18. Two complementary angles measure (4x + 9)° and (3x + 18)°. Find x.
  19. Two complementary angles measure (x)° and (4x + 30)°. Find x.
  20. Two complementary angles measure (4x + 5)° and (2x + 31)°. Find x.
More free practice: fieldbooklearning.com/uk/practice/year-8/write-and-solve-equations-complementary-angles/

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Answer key: Write and solve equations: complementary angles

  1. 11
  2. 9
  3. 13
  4. 15
  5. 18
  6. 12
  7. 11
  8. 19
  9. 10
  10. 8
  11. 12
  12. 17
  13. 6
  14. 8
  15. 10
  16. 15
  17. 24
  18. 9
  19. 12
  20. 9