SOLUTION: 3x - 8y = 2 4x - 4y = 32

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Question 621375: 3x - 8y = 2
4x - 4y = 32
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
system%283x+-+8y+=+2%2C4x+-+4y+=+32%29

A combination equation (made by multiplying equations times factors as needed and adding them) can replace one of the equations in a system to make an equivalent system.
system%283x+-+8y+=+2%2C4x+-+4y+=+32%29 --matrix%282%2C1%2C%22times+%28-1%29%22%2C+%22times%282%29%22%29--> --> 5x=62 --> 5x%2F5=62%2F5 --> highlight%28x=62%2F5%29
system%28x=62%2F5%2C4x+-+4y+=+32%29 --matrix%282%2C1%2C%22times+1%22%2C+times+%28-1%2F4%29%29--> --> y=62%2F5-40%2F5 --> highlight%28y=22%2F5%29

SOLVING BY SUBSTITUTION
4x-4y=32 --(dividing both sides by 4)--> x-y=8 --> x-y%2By=8%2By --> x=y%2B8
3x-8y=2 --(multiplying both sides by (-1)) --> -3x%2B8y=-2
and substituting the expression for x found before
-3x%2B8y=-2 --> -3%28y%2B8%29-8y=-2 --> -3y-24%2B8y=-2 --> -24%2B5y=-2 --> -24%2B5y%2B24=-2%2B24 --> 5y=22 --> 5y%2F5=2%2F52 --> highlight%28y=22%2F5%29
and that value can be substituted in x=y%2B8 to get
x=22%2F5%2B8 -->x=22%2F5%2B40%2F5 --> highlight%28x=62%2F5%29