SOLUTION: Solve using substitution. 2x + y = -9 so this is what I tried... 2x - 2x -9 = -9 -2x -2x

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Question 369085: Solve using substitution.
2x + y = -9 so this is what I tried... 2x - 2x -9 = -9
-2x -2x
-2x -9 = -2x -9
+9 +9
-2x = -2x???? What am I doing wrong?
y= -2x -9
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
You're not doing anything wrong except that you only have 1 equation with 2 unknowns.
You can only solve for one variable in terms of the other variable.