x^2(x-10)+4(x-10)=0
(x-10)(x^2+4)=0
x^3-10x^2+4x-40=0
(x^3-10x^2) + (4x-40) = 0
x^2(x-10) + 4 (x-10) = 0
x-10 = 0 или x^2+4 = 0
x=10 или x^2=-4 => корней нет
ответ: х=10
x^2(x-10)+4(x-10)=0
(x-10)(x^2+4)=0
x^3-10x^2+4x-40=0
(x^3-10x^2) + (4x-40) = 0
x^2(x-10) + 4 (x-10) = 0
(x-10)(x^2+4)=0
x-10 = 0 или x^2+4 = 0
x=10 или x^2=-4 => корней нет
ответ: х=10