Use a matrix to find the solution to the system of equations.

Question

{-8x - 8y = -16
{6x - 9y = -108
A.(-6,8)
B.(6,8)
C.(8,-6)
D.(6,-8)

Answer 1

First I'd factor out what I could to make the system
x+y = 2
2x-3y = -36
So, now you have
AX=B
where
A = {{1,1},{2,-3}} and B={{2},{-36}}
so A^-1 = 1/5 {{3,1},{2,-1}}
and we have
X = A^-1*B = 1/5 {{3,1},{2,-1}}*{{2},{-36}} = {{-6},{8}}
so (-6,8) is the solution

Answer 2

I just used this answer and it is correct