SOLUTION: 3x-5y=0 and 9x+84=y solve with substutution method can you please explain because I am having a hard time and I need to understand.

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Question 473234: 3x-5y=0 and 9x+84=y solve with substutution method can you please explain because I am having a hard time and I need to understand.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
3x-5y=0 and 9x+84=y solve with substutution method
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Substitute for "y" and solve for "x":
3x-5(9x+84) = 0
3x-45x-420 = 0
-42x = 420
x = -10
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Solve for "y":
y = 8x+84
y = 8*-10+84
y = 4
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Solution: (-1,4)
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Cheers,
Stan H.