SOLUTION: solve each equation by using the substitution method and the elimination method 2x+3y=0 4x+12=9y

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Question 348530: solve each equation by using the substitution method and the elimination method
2x+3y=0
4x+12=9y
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Substitution:
1.2x%2B3y=0
2.4x-9y=-12
From eq. 1,
2x=-3y
-9y=6x
Substitute into eq. 2,
4x-9y=-12
10x=-12
highlight%28x=-6%2F5%29
Then from eq. 1,
-9y=6%28-6%2F5%29
-9y=-36%2F5
highlight%28y=4%2F5%29
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.
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Elimination:
1.2x%2B3y=0
2.4x-9y=-12
Multiply eq. 1 by 3 and add the equations together,
6x%2B9y%2B4x-9y=-12
10x=-12
highlight%28x=-6%2F5%29
Then from eq. 1,
-9y=6%28-6%2F5%29
-9y=-36%2F5
highlight%28y=4%2F5%29