Question

Решите два уравнения.

Answer 1

• $frac{5x-2}{x+2}=frac{6x-21}{x-3}\(5x-2)(x-3)=(6x-21)(x+2)\5x^2-17x+12=6x^2-9x-42\x^2+8x-54=0\D=64+216=280=(2sqrt{70})^2\left.begin{array}{cc}x_1=-4+sqrt{70}&x_2=-4-sqrt{70}end{array}right.$

• $frac9{x+3}=2x-1\9=(2x-1)(x+3)\2x^2+5x-12=0\D=25+96=121=11^2\x_1=frac{-5-11}4=-4\x_2=frac{-5+11}4=1.5$