Question

9x*-3x=3(12-2x)
$9x {?}^{2} - 3x = 3(12 - 2x)$
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Answer 1

$9 {x}^{2} - 3x = 3(12 - 2x) \\ 9 {x}^{2} - 3x = 36 - 6x \\ 9 {x}^{2} + 3x - 36 = 0 \\ 3 {x}^{2} + x - 12 = 0 \\ d = {1}^{2} - 4 \times 3 \times ( - 12) = 145 \\ x_{1} = \frac{ - 1 + \sqrt{145} }{6} \\ x_{2} = \frac{ - 1 - \sqrt{145} }{6}$