Find the value of y for the following system of equations. -x - y = 7 x - y = 9

y = -8

Step-by-step explanation:

It is given that,

-x - y = 7  ---(1)

x - y = 9  ---(2)

To find the solution

Add eq (1) and eq(2) we get

-x - y = 7  ---(1)

x - y = 9  ---(2)

0 - 2y  = 16

y = 16/(-2) =  -8

Substitute the value of y in eq(1)

-x - y = 7  ---(1)

-x - -8 = 7

-x + 8 = 7

x = 8 - 7 = 1

Therefore x = 1 and y = -8

72 is the answer to this problem