SOLUTION: I am having trouble with this equation, 8x-9y=8.5 7y-2x=-45 solve using the elimination method. Can you explain how to do this? (In layman's terms)

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Question 309631: I am having trouble with this equation,
8x-9y=8.5
7y-2x=-45
solve using the elimination method.
Can you explain how to do this? (In layman's terms)
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
8x-9y=8.5
7y-2x=-45
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Rearrange:
8x-9y = 8.5
-2x+7y = -45
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Let's say you want to eliminate the x-terms.
Multiply thru the 2nd equation by 4 to get:
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8x-9y = 8.5
-8x+28y = 4*-45
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Add the two equations:
19y = -171.5
y = -9.0263
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Substitute that into either of the original equations and solve for "x":
7y-2x = -45
7y - 2(-9.0263) = -45
7y = -63.0526
y = -9.0075
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You could check the answers in the other original equation.
You have to realize some accuracy is lost because the decimal
results were rounded.
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8x-9y=8.5
8*-9.0263 -9(-9.0075) =8.5
8.8571 is close to 8.5
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Cheers,
Stan H.