Question

Помогите решить уравнение: (6x + 5) x (-5x + 6) = 0

Answer 1

$\displaystyle\bf\\(6x+5)\cdot(-5x+6)=0\\\\6x\cdot(-5x)+6x\cdot 6+5\cdot(-5x)+5\cdot6=0\\\\-30x^{2} +36x-25x+30=0\\\\-30x^{2} +11x+30=0\\\\30x^{2} -11x-30=0\\\\D=(-11)^{2} -4\cdot 30\cdot(-30)=121+3600=3721=61^{2} \\\\\\x_{1}=\frac{11-61}{60} =-\frac{50}{60} =-\frac{5}{6} \\\\\\x_{2} =\frac{11+61}{60} =\frac{72}{60} =1,2\\\\\\Otvet \ : \ -\frac{5}{6} \ \ ; \ \ 1,2$