SOLUTION: Solve -3x+5y=21 and 6x-y=-15

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Question 1205753: Solve -3x+5y=21 and 6x-y=-15
Found 2 solutions by MathLover1, josgarithmetic:
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

-3x%2B5y=21......eq.1.....both sides multiply by 2
6x-y=-15........eq.2
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-6x%2B10y=42......eq.1
6x-y=-15........eq.2
--------------------------------add
-6x%2B10y%2B6x-y=42-15
9y=27
y=3
go to
6x-y=-15........eq.2, substitute y
6x-3=-15
6x=-15%2B3
6x=-12
x=-2


Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
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Solve -3x+5y=21
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Nothing appears wrong with it needing to be solved.

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and 6x-y=-15
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That one looks good too.


system%28-3x%2B5y=21%2C6x-y=-15%29 AS A SYSTEM,

system%28y=6x%2B15%2C-3x%2B5y=21%29

-3x%2B5%286x%2B15%29=21

-3x%2B30x%2B75=21

27x=21-75

27x=-54

highlight%28x=-2%29
-
y=6x%2B15
y=-12%2B15
highlight%28y=3%29