What is the solution of the system?

Question

Solve the system of equations using the substitution method.
x-y=-1
5x+4y=-23

Answer 1

Eqn (1) to be mly by 4,
then we have 4x-4y=-4,
(2)5x+4y=-23
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9x+ 0=-27
9x=-27
x=-27/9=-3
x=-3.
to get y,
we substitute in the eqn(1)
(x-y=-1) as -3-y=-1
-3+1=y
y=-2.

Therefore, we get x=-3
y=-2