Consider the following pair of equations:
y = −2x + 8
y = x − 1
explain how you will solve the pair of equations by substitution. show all the steps and write the solution in (x, y) form.

Okay so you use the bottom to substitute y so your equation will be:
x-1=2x+8 now solve for x
-x-8=-x-8 this is what you will be taking away from both sides
-1-8=2x-x this is your new equation now you just do basic math
-9=x this is x
Now that you found x find y by substituting x
y=2(-9)+8
y= -18+8
y= (-10) this is your y
Now to check your answer on the other equation
y= -9-1
y= (-10) this is now correct
(x,y)form is (-9,-10)
Hopefully i helped out