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Year 9 Simultaneous Equations Worksheet — Level 2 — Answers

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Success TutoringWorksheetsAnswer sheetYear 9 · Mathematics · Simultaneous Equations

Year 9 Simultaneous Equations Worksheet — Level 2 — Answers

Solve each pair of equations. Check your solution satisfies both equations.

1.Solve simultaneously: 3x + 2y = 9 and 3x − 3y = −21

Answer: x = −1, y = 6

  1. Subtract equation 2 from equation 1: 5y = 30
  2. y = 6
  3. Substitute into equation 1: 3x + 12 = 9, so x = −1
2.Solve simultaneously: 3x + 3y = 21 and 3x − 4y = −21

Answer: x = 1, y = 6

  1. Subtract equation 2 from equation 1: 7y = 42
  2. y = 6
  3. Substitute into equation 1: 3x + 18 = 21, so x = 1
3.Solve simultaneously: 3x + 4y = 21 and 3x − 5y = −33

Answer: x = −1, y = 6

  1. Subtract equation 2 from equation 1: 9y = 54
  2. y = 6
  3. Substitute into equation 1: 3x + 24 = 21, so x = −1
4.Solve simultaneously: 4x + 3y = 34 and 4x − 4y = 20

Answer: x = 7, y = 2

  1. Subtract equation 2 from equation 1: 7y = 14
  2. y = 2
  3. Substitute into equation 1: 4x + 6 = 34, so x = 7
5.Solve simultaneously: 3x + 3y = 33 and 3x − 4y = −9

Answer: x = 5, y = 6

  1. Subtract equation 2 from equation 1: 7y = 42
  2. y = 6
  3. Substitute into equation 1: 3x + 18 = 33, so x = 5
6.Solve simultaneously: 3x + y = 19 and 3x − 2y = −2

Answer: x = 4, y = 7

  1. Subtract equation 2 from equation 1: 3y = 21
  2. y = 7
  3. Substitute into equation 1: 3x + 7 = 19, so x = 4
7.Solve simultaneously: 3x + 4y = 10 and 3x − 3y = 3

Answer: x = 2, y = 1

  1. Subtract equation 2 from equation 1: 7y = 7
  2. y = 1
  3. Substitute into equation 1: 3x + 4 = 10, so x = 2
8.Solve simultaneously: 3x + 3y = 3 and 3x − 4y = −32

Answer: x = −4, y = 5

  1. Subtract equation 2 from equation 1: 7y = 35
  2. y = 5
  3. Substitute into equation 1: 3x + 15 = 3, so x = −4
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