Question

18х2-9х-5=0


как решать??????​

Answer 1

$18x^2-9x-5=0\\\\D=(-9)^2-4*18*(-5)=81+360=441=21^2\\\\x_1=\frac{9+21}{2*18}=\frac{30}{2*18} =\frac{5}{6} \\\\x_2=\frac{9-21}{2*18}=\frac{-12}{2*18} =-\frac{1}{3}$