1,2+0,4x-2,4y
2x=3y+5
x=(3y+5)/2
1,2+0,4x-2,4y=1,2+(0,4*(3y+5)/2)-2,4y=1,2+0,2*(3y+5)-2,4y=1,2+0,6y+1-2,4y=2,2-1,8y
3y=-5+2x
3y=-5+2(2,2-1,8y)
3y=-5+4,4-3,6y
3y=0,6-3,6y
6,6y=0,6
y=6/66
2,2-1,8y=2,2-1,8*6/66=2,2-1,8*1/11=2,2-1,8/11= (24,2-1,8)/11=22,4/11=224/110=2 целых 4/110=2 целых 2/55