5х/4 * 8/х = 40х/4х = 10.............
20у-12у-у-2у=<span>20у-12у-1у-2у</span>=у(20-12-1-2)=5у
1) 5=-3(2х+1) +2(4х+2)
5=-6x-3+8x+4
5+3-4=2x
4=2x
x=2
2)(2х-3) +3(2х+3) =23
2x-3+6x+9=23
2x+6x=23-9+3
8x=17
x=17/8