Question

Решите плиз
x(10x-14)=9

Answer 1

$x(10x-14)=9 \ 10 x^{2} -14x-9=0 \ D=196+360=556 \ sqrt{D} = sqrt{556}$

$x_{1} = frac{14+ sqrt{556} }{20} \ x_{2} = frac{14- sqrt{556} }{20}$