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How To Solve Equation By Elimination 2x-4y=-4 3x+2y=18?

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Oddman answered
To eliminate y, double the second equation and add it to the first.
   2(3x + 2y) + (2x - 4y) = 2(18) + (-4)
   8x = 32
   x = 4

You can solve for y by substituting this value into either equation.
   2(4) - 4y = -4
   12 - 4y = 0
   3 - y = 0
   3 = y
The solution is (x, y) = (4, 3).
You can eliminate x by multiplying the first equation by 3 and subtracting that from twice the second equation. The idea of doing the multiplications is to make the coefficients of the x terms in the product be the same. Then, when you do the subtraction, they cancel.
   2(3x + 2y) - 3(2x - 4y) = 2(18) - 3(-4)
   6x + 4y - 6x + 12y = 36 + 12
   16y = 48
   y = 3

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