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Algebra Difficulty 3.8 AMC 10/12 Find the answer South Africa

The values of xx satisfying the equation (x7)(x+12)=48(x - 7)(x + 12) = -48 are

Pick one

Solution

Multiplying out the equation gives x2+5x84=48x^2 + 5x - 84 = -48, so x2+5x36=0x^2 + 5x - 36 = 0. This factorizes to (x+9)(x4)=0(x + 9)(x - 4) = 0, so x=9x = -9 or x=+4x = +4.

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