Question

If two equations are 3x + 2y = 14; 5x + 3y = 12, then the value of
5x – y is

Answer 1

-124

Explanation:

3x + 2y = 14 (×3) → 9x + 6y = 42

- → x = -18

5x + 3y = 12 (×2) → 10x + 6y = 24

3(-18) + 2y = 14

-54 + 2y = 14 → 2y = 14 + 54 = 68 → y = 68/2 = 34

5x - y = 5(-18) - 34 = -90 - 34 = -124