SOLUTION: Can you help me to solve this equation by using substitution method. 6x + 3y = 0 -3x + 3y = 9

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Question 857753: Can you help me to solve this equation by using substitution method.
6x + 3y = 0
-3x + 3y = 9

Found 2 solutions by stanbon, rothauserc:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
solve this equation by using substitution method.
6x + 3y = 0
-3x + 3y = 9
-------
3y = 3x+9
----
Substitute for "3y" and solve for "x":
6x + 3x+9 = 0
9x = -9
x = -1
-----
Solve for "y":
y = x + 3
y = -1=3
y = 2
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Cheers,
Stan H.
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Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
we are given the following
6x + 3y = 0
-3x + 3y = 9
solve second equation for y
3x +9 = 3y
y = x + 3
substitute for y in first equation
6x + 3(x+3) = 0
6x + 3x + 9 = 0
9x = -9
x = -1
substitute for x in second equation
-3(-1) +3y = 9
3y = 6
y = 2
answer is x = -1 and y = 2