Question

Решите уравнение x(x^2+8x+16)=5(x+4)​

Answer 1

$x(x^2+8x+16)=5(x+4)\\x^3+8x^2+16x=5x+20\\x^3+8x^2_16x-5x-20=0\\x^3-x^2+9x^2+11x-20=0\\x^3-x^2+9x^2-9x+20x-20=0\\x^2(x-1)+9x(x-1)+20(x-1)=0\\(x-1)(x^2+9x+20)=0\\(x-1)(x^2+5x+4x+20)=0\\(x-1)(x(x+5)+4(x+5))=0\\(x-1)(x+5)(x+4)=0\\x-1=0\\x_1=1\\x+5=0\\x_2=-5\\x+4=0\\x_3=-4$

Answer 2

Ответ:

x (x+4)2=12,x (x+4)=12,x2+x4-12=0, (x+6)(x-2)=0,x=-6,x2