Solve the system of linear equations by substitution x+4y =37 y = -x + 16

1 answer:

4 0

You plug -x+16 in for y in x+4y=37 to get x after you multiply x+4y=37 by -1.
-x-4(-x+16)=-37
-x+4x-64=-37
3x-64=-37
3x=27
x=9
Then you plug 9 into either equation to get y.
y=-x+16
y=-(9)+16
y=7

x=9 and y=7

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sarah can complete a project in 90 minutes and her sister betty can complete it in 120 minutes if they both work on the project

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