1)x²-100x=0,x(x-100)=0, x1=0,x2=100
2)9/25x³-x=0, x(9/25x²-1)=0,x((3x/5)²-1²)=0,x(3x/5+1)(3x/5-1)=0
x1=0,x2=-5/3,x3=5/3
3)25y²+20y+4=0,(5y+2)(5y+2)=0, y=-2/5
4)36x²+25=60x,36x²ˇ-60x+25=0,(6x-5)²=0,x=5/6
<span>ЕНТО факториал
n!=1*2*3*4*....*(n-1)*n
7!+8!/5!+6!=1*2*3*..*7+1*2*...*8/1*2*3*4*5+1*2*3*4*5*6=5040+6*7*8+720=5040+336+720= 6096</span>
X2-2x-8=0
D=4+32=36
x1=2+6/2=4
x2=2-6/2=-2
Ответ: -2;4