SOLUTION: Solve by substitution. X=12-y 6x-3y=9

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Question 823057: Solve by substitution.
X=12-y
6x-3y=9
Found 2 solutions by faceoff57, ewatrrr:
Answer by faceoff57(108) About Me  (Show Source):
You can put this solution on YOUR website!
Solve by substitution.
X=12-y
6x-3y=9
6(12 - y) - 3y = 9
72 - 6y - 3y = 9
-9y = 9 - 72
-9y = -63
Y = 7
X = 12 - 7
X = 5
(5,7)

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

Solve by substitution.

x = 12-y

6x-3y=9    |Substituting for x

6(12-y) - 3y = 9 

    -9y = -63

      y = 7

and   x = 5    12-y     

CHECKING our answer***

using: 6x-3y=9 

    30 - 21 = 9