SOLUTION: 3x-10y=-25 4x+40y=-5 how do you solve these by elimination?

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Question 565863: 3x-10y=-25
4x+40y=-5
how do you solve these by elimination?

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


Multiply both sides of the first equation by 4 so that the coefficient on in the first equation will be the additive inverse of the coefficient on in the second equation. Then add the two equations term by term and the term will be eliminated (hence the name of the method) leaving you with a single equation in one variable. Solve for and then substitute this value back into either of the original equations and solve for .

There is nothing sacred about eliminating the variable. You could also eliminate the variable instead. Multiply the first equation by 4 and the second by -3. That would make the coefficients on be 12 and -12.

John

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