SOLUTION: Solve by the elimination method. 9x-9y=27 7y-3x= -11 What is the solution of the system?

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Question 161198: Solve by the elimination method.
9x-9y=27
7y-3x= -11
What is the solution of the system?
Answer by jojo14344(1513) About Me  (Show Source):
You can put this solution on YOUR website!

9x-9y=27 --------------> eqn 1
7y-3x=-11 ------------> eqn 2
Multiply eqn 2 by highlight%283%29:
7y-3x=-11-------> 21y-9x=-33 -----> eqn 3
Add eqn 1 & eqn 3:
12y=-6 ----> system%289x-9y=27%2C21y-9x=-33%29, eliminates 9x
Continuing,
cross%2812%29y%2Fcross%2812%29=-6%2F12=-1%2F2 divide 12 to isolate y
y=-1%2F2
via eqn 1:
9x-9%28-1%2F2%29=27
9x%2B9%2F2=27
9x=27-9%2F2=%2854-9%29%2F2 get LCD of left term
18x=45, cross multiply
cross%2818%29x%2Fcross%2818%29=cross%2845%292.5%2Fcross%2818%29
x=2.5
(2.5,-0.5) ANSWER
Check via eqn 2:
7%2A-1.5-3%2A2.5=-11
-3.5-7.5=-11
-11=-11
Thank you,
Jojo