3y^2-12y=3y(y-4)
ab-2a+b^2-2b=a(b-2)+b(b-2)=(b-2)(a+b)
4x^2-9=(2x-3)(2x+3)
x^3-8x^2+16x=x(x^2-8x+16)=x(x-4)^2
6n^3+6m^3=6(n^3+m^3)=6(n+m)(n^2+mn+m^2)
16m^4-81n^4=(4m^2-9n^2)(4m^2+9n^2)=(2m-3n)(2m+3n)(4m^2+9n^2)
(x-4)^2-25=0
(x-4-5)(x-4+5)=0
(x-9)(x+1)=0
x=9
x=-1
ответ: 9 и -1
3y^2-12y=3y(y-4)
ab-2a+b^2-2b=a(b-2)+b(b-2)=(b-2)(a+b)
4x^2-9=(2x-3)(2x+3)
x^3-8x^2+16x=x(x^2-8x+16)=x(x-4)^2
6n^3+6m^3=6(n^3+m^3)=6(n+m)(n^2+mn+m^2)
16m^4-81n^4=(4m^2-9n^2)(4m^2+9n^2)=(2m-3n)(2m+3n)(4m^2+9n^2)
(x-4)^2-25=0
(x-4-5)(x-4+5)=0
(x-9)(x+1)=0
x=9
x=-1
ответ: 9 и -1