Question

A) x/3 -9/x=-2
ME AJUDEM

Answer 1

$\frac{x}{3} - \frac{9}{x} =-2 \\ \\ \frac{x\cdot x-9\cdot3}{3x} =-2 \\ \\ x^{2} -27=(-2)3x \\ \\ x^{2} +6x-27=0$

Resolvendo a equação do segundo grau:

$\Delta = 6^{2} -4\cdot1\cdot(-27) \\ \Delta = 36+108 \\ \Delta=144$

$x= \frac{-6\pm \sqrt{144} }{2} \\ \\ x= \frac{-6\pm12 }{2} \\ \\ x=-3\pm6$

$x_{1}=3 \\ \\ x_{2}=-9$

S = {-9, 3}