1) x^2-4x=0
x=4 x=0
2) (7x-5)/(x+1)-(4+x)/x=1/9
(6x^2-10x-4)/(x^2+x)=1/9
54x^2-90x-36=x^2+x
53x^2-91x-36=0
x=(91+-sqrt(15913))/106
x1~=2,05
x2~=-0,33
(6х-4)∙5≥(5х-4)∙6
30x-20≥30x-24
-20≥-24 => x - любое
=(5y-4x-5y)/20xy=-4x/20xy=-1/5y
X²-5x=14
x²-5x-14=0
D=5²-4*1*(-14)=25+56=√81=9
x1=
![\frac{5+9}{2}](https://tex.z-dn.net/?f=+%5Cfrac%7B5%2B9%7D%7B2%7D+)
=7
x2=
![\frac{5-9}{2}](https://tex.z-dn.net/?f=+%5Cfrac%7B5-9%7D%7B2%7D+)
=-2
Ответ:7;-2