<span>(х-1)(х+3)=х(х-2),
х</span>²+3х-х-3=х²-2х,
<span>3х-х-3=-2х,
2х-3=-2х,
2х+2х=3,
4х=3,
х=3:4,
х=0,75.
Ответ: 0,75.</span>
..................................................................
<span>√(5<span>x+20) - √(x+8 )= 2
</span></span>√(5x+20) = 2+√(x+8)
5x+20 = 4+ 4√(x+8) + x + 8
5x+20-4-x-8= 4√(x+8)
4x+8=4√(x+8)
16x^2+64x+64-16x-128=0
16x^2+48x-64=0
x^2+3x-4=0
x(1)=4
x(2)=-1
X^2<25 по свойству степеня
|x|<5
-5<x<5
1)(4х²+4х+1)/4х=(2х+1)²/4х
2)(4х²-1)/4х
3)(2х+1)²/4х:(4х²-1)/4х=(2х+1)²*4х/4х*(2х-1)(2х+1)=(2х+1)/(2х-1)=
=(23+1)/(23-1)=24/22=12/11=1 1/11