SOLUTION: solve the system: 3x+4y=40 x-2y=0 solve the system: 3x+4y=-2 x=-2y

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Question 522412: solve the system:
3x+4y=40
x-2y=0
solve the system:
3x+4y=-2
x=-2y
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


For the first one, multiply the 2nd equation by 2, then add the two equations, term by term. The y variable will end up with a zero coefficient and you can then solve the single variable equation in x. Once you know x, substitute it back into either of the original equations and solve for y.

For the second one, read the instructions for posting.

John

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