Question

Solve for x and y
-2x-y=-9
5x-2y=-9

Answer 1

we use equation 1 first.
-2x -y = -9

-y = -9 + 2x

y = 9 -2x

We substitute value of y in equation 2

5x - 2 (9 - 2x) = -9

5x -18 - 4x = -9

5x - 4x = -9 + 18

x = 18 -9

x = 9

We now find the value of y

-2x -y = -9

-2 (9) - y = -9

-18 - y = -9

-y = -9 + 18

y = 9 - 18

y = -9