przypuszczam ze powinno byc: x-2/5-2y=5 (chyba źle napisałaś) a więc:
a)x-2y=5+ 2/5
x-y=3-2/6
x-2y= 5 2/5
x-y= 2 4/6
x=5 2/5 +2y
5 2/5+2y=2 4/6
x=5 2/5+2y
2y= 2 4/6-5 2/5
x=5 2/5+2y
2y= 2 20/30- 5 12/30
x=5 2/5+2y
2y= -98/30 /:2
x=5 2/5+2y
y= - 49/30
x= 5 2/5 + 2* - 49/30
y= - 49/30
x=5 12/30 +3 8/30
y= - 49/30
x= 8 2/3
y= - 49/3
b) x+ y/2-x/3=4 /*6
x- y/2 + y/3=-3/*6
6x+3y-2x=24 (skresl to 3y i -3y poniewaz sie redukuje )
6x-3y+2y=-3
4x=24/:4
6x+2y=-3
x=6
6*6+2y=-3
x=6
36+2y= -3
x=6
2y= -3-36/:2
x=6
y=-19,5
