У+(9,31-7цел.1/4)=8,2 (7,43-2цел.3/25)+х=7 (8,61-3цел.3/4)+у=1

1) 7 1/4 =29/4 =7.25
y +(9.31 -7.25) =8.2
y +2.06 =8.2
y = 8.2 -2.06
y = 6.14

2) 2 3/25 =53/25 =2.12
7.43 -2.12 +x =7
5.31 +x =7
x =7-5.31
x =1.69

3) 3 3/4 =15/4 =3.75
8.61 -3.75 +y =1
4.86 +y =1
y =1 -4.86
y = -3.86