Question

$x(x - 2) = 2(x + 6)$
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Answer 1

$x(x - 2) = 2(x + 6) \\ {x}^{2} - 2x =2x + 12 \\ {x}^{2} - 2x - 2x - 12 = 0 \\ {x}^{2} - 4x - 12 = 0$

$\Delta = {b}^{2} - 4ac \\ \Delta = {( - 4)}^{2} - 4.1.( - 12) \\ \Delta = 16 + 48 \\ \Delta = 64$

$x = \frac{-b±\sqrt{\Delta} }{2a} \\ x = \frac{ - ( - 4)± \sqrt{64} }{2.1} \\ x = \frac{4±8}{2}$

$x' = \frac{4 + 8}{2} = \frac{12}{2} = 6 \\ x'' = \frac{4 - 8}{2} = - \frac{4}{2} = - 2$

s={6,-2}