A)(x^2)/x+3=(2x+3)/x+3, x≠-3
x^2=2x+3
x^2-2x-3=0
D=(-2)^2-4×1×(-3)=4+12=16
x1=(2-√16)/(2×1)=(2-4)/2=-2/2=-1
x2=(2+^16)/(2×1)=(2+4)/2=6/2=3
Ответ: x1=-1, x2=3
б)(2x)/(x+6)-(144)/(x-6)(x+6)=1
(2x(x-6)-144)/(x-6)(x+6)=1
2(x^2-6x-72)/(x-6)(x+6)=1
2(x^2+6x-12x-72)/(x-6)(x+6)=1
2(x(x+6)-12(x+6))/(x-6)(x+6)=1
2(x+6)(x-12)/(x-6)(x+6)=1
2(x-12)/(x-6)=1
2x-24=x-6
2x-x=-6+24
x=18