Question 150729: 5x-2y=-16
2x+ y= 8
please solve using elimination method
Answer by Electrified_Levi(103)   (Show Source):
You can put this solution on YOUR website! Hi, Hope I can help
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5x-2y=-16
2x+ y= 8
please solve using elimination method
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elimination method is pretty easy, first you either add or subtract the equations to get rid of a letter
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We can't add or subtract to get rid of a letter, yet.
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We will add the first two equations to make a new equation
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5x-2y=-16
2x+ y= 8
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5x-2y=-16
+ (2x + y= 8)
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5x-2y=-16
+ 2x+y= +8
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We can move the second equation to the first equation
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It will become
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We can now add or subtract to get rid of a letter, which is "y"
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We can add the second equation (2x+ y= 8) to our third equation ( 7x - y = -8 )
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We will put them side by side
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7x - y = -8
2x+ y= 8
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We will now add
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7x - y = -8
+ (2x + y = 8)
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7x - y = -8
+ 2x + y= + 8
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We will put the equations on top of each other
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It will become
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We will divide each side by 9
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x = 
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x = 0
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We can replace "x" in our original equations
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5x-2y=-16
2x+ y= 8
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We will use the second equation
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y = 8
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Our soulution is (0,8) (x,y) (point (0,8) can be put in both of our orignal equations)
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We can check by replacing "x" and "y" in our first equation, and second equation
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First equation
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 (True)
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Second equation
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 (True)
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Our solution set = (0,8)
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Hope I helped, Levi
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