<span>у²-36/у²-12у+36=(у+6)(у-6)/(у-6)(у-6)=(у+6)/(у-6)=(-2+6)/(-6-2)=-4/8=-0,5</span>
1/5 - (1/3x + 4,63) = 2/3x - 1/3 + 1,37
1/5 - 1/3x - 4,63 = 2/3x - 1/3 + 1,37
- 1/3x - 2/3x = - 1/5 + 4,63 - 1/3 + 1,37
- x = 6 - 8/15
- x = 5 7/15
x = - 5 7/15
2х+у=12
7х-2у=31
у=12-2х
7х-2(12-2х)=31
у=12-2х
7х-24+4х=31
у=12-2х
11х=55
х=5
у=12-10
у=2
=а²-4-а²-1=-4-1=-(4+1)=-5