SOLUTION: y-5=2x y-9=-2 Please tell me how to solve this problem by substitution.

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Question 51709: y-5=2x
y-9=-2 Please tell me how to solve this problem by substitution.
Answer by tutorcecilia(2152) About Me  (Show Source):
You can put this solution on YOUR website!
y-5=2x
y-9=-2 [Pick either equation and solve for y (or x)]
.
y-9=-2
y-9+9=-2+9 [Solve for y]
y=7
.
y-5=2x [Plug (y=7) back into the other equation]
(7)-5=2x
2=2x [Solve for x]
1=x
.
Plug the value for (y=7) and (x=1) into either equation]
y-5=2x
(7)-5=2(1)
2=2 [Checks out]
or
y-9=-2 [Plug-in (y=7)
(7)-9=-2
-2=-2 [Also checks out]