Question

solve each system by substitution.
y=-6
y=-2x-2
what is the solution?

Answer 1

They both have the same Y value, just found with different equations so you can make them equal to each other
-2x-2=-6
work from there

Answer 2

y=-6
y=-2x-2
plug in y in the equation
-6=-2x-2
subtract -2 from both sides
-4=-2x
x=2

Answer 3

You mean add 2 to both sides, otherwise correcet

Answer 4

yes that is what I meant.