3 years ago

3x+7y=-1 and 4x-3y=11 solve by elimination/linear combination

1 answer:

7 0

Solution:

1) Solve for x in 3x+7y=-1
x=\frac{-1-7y}{3}

2) Substitute x=\frac{-1-7y}{3} into 4x-3y=11
\frac{4(-1-7y)}{3}-3y=11

3) Solve for y in \frac{4(-1-7y)}{3}-3y=11
y=-1

4) Substitute y=-1 into x=\frac{-1-7y}{3}
x=2

5) Therefore,
x=2
y=-1

Done!

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