SOLUTION: y=4X+12 -4X+3y=21

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Question 948955: y=4X+12
-4X+3y=21
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Substitute from the first equation into the second.
y=4X%2B12
4X=y-12
.
.
-%28y-12%29%2B3y=21
-y%2B12%2B3y=21
2y=9
y=9%2F2
Then,
4X=9%2F2-12
4X=9%2F2-24%2F2
4X=-15%2F2
X=-15%2F8