SOLUTION: solve the linear system: x-2y=-5 , -3x+y=0 I need step by step help.

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Question 397052: solve the linear system: x-2y=-5 , -3x+y=0 I need step by step help.
Found 2 solutions by stanbon, josmiceli:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
solve the linear system: x-2y=-5 , -3x+y=0
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x-2y = -5
-3x+y = 0
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Multiply thru the 1st equation by 3 to get:
3x-6y = -15
-3x+y = 0
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Add and solve for "y":
-5y = -15
y = 3
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Solve for "x":
x-2y = -5
x-2(3) = -5
x-6 = -5
x = 1
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Solution: (1,3)
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Cheers,
Stan H.
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Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Hi,
(1) x+-+2y+=+-5
(2) -3x+%2B+y+=+0
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The most important rule is:
"What ever you do to one side of an equation,
you must do to the other side."
Multiply both sides of (2) by 2
then add the equations
(1) x+-+2y+=+-5
(2) -6x+%2B+2y+=+0 (notice that 2%2A0+=+0)
-5x+=+-5
x+=+1
Now substitute this value in (1)
(1) 1+-2y+=+-5
Subtract 1 from both sides
-2y+=+-5+-+1
-2y+=+-6
Divide both sides by -2
y+=+3
The solution is (1,3)