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South African Mathematics Olympiad

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

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

Pick one

Solution

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

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