Question

Solve the following system of equations.
- 2x+7y=9
3x - 4y=-20

Answer 1

y = -1

x = -8

Explanation:

-2x+7y=9 / *3

3x - 4y=-20 / *2

-6x+21y = 27

6x - 8y = -40

-6x +6x + 21y - 8y = 27 - 40

13y = -13

y = -1

-2x + 7*(-1) = 9

-2x -7 = 9

-2x = 9+7

-2x = 16

-x = 8

x = -8