SOLUTION: Solve the system by addition. 4x – 6y = –1 8x + 3y = 3

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Question 108482: Solve the system by addition.
4x – 6y = –1
8x + 3y = 3

Answer by elima(1433) About Me  (Show Source):
You can put this solution on YOUR website!
4x – 6y = –1
8x + 3y = 3
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This is also called elimination, you want to eliminate one of the variables.
So we will try to eliminate the x, so I will multiply the first equation by -2,
(-2)4x-6y=-1
-8x+12y=2----new equation
Now lets take the new equation and add it to the original second;
cross+%28-8x%29%2B12y=2
cross+++%288x%29%2B3y=3
_________
15y=5
y=5%2F15
y=1%2F3
Now we will plug y=1/3 into one of the original equations for y;
4x-6(1/3)=-1
4x-2=-1
4x=1
x=1/4
check:
4(1/4)-6(1/3)=-1
1-2=-1
:)