при каких значениях х значения данной дроби равны

$\frac{18-6x^{2} }{5-x} = \frac{x^{2}-15x }{5-x} \\ \frac{18-6x^{2} }{5-x} - \frac{x^{2}-15x }{5-x}=0 \\ \frac{18-6x^{2}- x^{2} +15x }{5-x}=0 \\ \frac{-7x^{2} +15x+18 }{5-x}=0 \\ \left \{ {{{-7x^{2} +15x+18=0} \atop {5-x \neq 0}} \right.$
$\left \{ {{{-7x^{2} +15x+18=0} \atop {x \neq 5}} \right. \\ \\ -7x^{2} +15x+18=0 \\ D=15^{2}-4*(-7)*18=225+504=729=27^{2} \\ x_{1}= \frac{-15+ \sqrt{729} }{2*(-7)} = \frac{-15+27}{-14} = \frac{12}{-14} = - \frac{6}{7} \\ x_{2}= \frac{-15- \sqrt{729} }{2*(-7)} = \frac{-15- 27}{-14} = \frac{-42}{-14} =3 \\$

x=3
x=-6/7
x не равно 5