Solve the equation 2x - 3y = 22; 3x + 2y = 7

  • A -5
  • B -4
  • C 4
  • D 5
waec 2005mathematics

The correct answer is B. -4

2x - 3y = 22 ---- eqn I

3x + 2y = 7 ---- eqn II

multiply eqn I by 2

4x - 6y = 44 ---- eqn III

multiply eqn II by 3

9x + 6y = 21 ---- eqn IV

Adding eqn III and IV

=> 13x = 65 => x = 5

Substituting 5 for x in eqn II

3x5 + 2y = 7 => 2y = -8

y = -4

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