X^3-3x^2-4x+12=0
x^2(x-3)-4(x-3)=0
(x^2-4)(x-3)=0
(x-2)(x+2)(x-3)=0
x-2=0
x1=2
x+2=0
x2=-2
x-3=0
x3=3
2+(-2)+3=3
Ответ: 3
(1/4)^(4x-10) = (1/4)^2
4x - 10 = 2
4x = 12
x = 3
(3х-8)²+(4х-8)(4х+8)+100х = 9х²-48х+64+16х²-64+100х = 25х²+52х
25х²+52х = 25*(-2)²+52*(-2) = 100-104 = -4