Решите уравнения надо d + 1/5 = 4/7 + 3/7 f + 4/5 = 4/7 + 3/7 b + 2/5 = 4/7 + 3/7 например 3/3 это я так зделал дробь

D + 1/5 = 4/7 + 3/7
d + 1/5 = 7/7
d + 1/5 = 1
d = 1 - 1/5
d = 5/5 - 1/5
d = 4/5

4/5 + 1/5 = 4/7 + 3/7
5/5 = 7/7
1=1

f + 4/5 = 4/7 + 3/7
f + 4/5 = 7/7
f + 4/5 = 1
f = 1 - 4/5
f = 5/5 - 4/5
f = 1/5

1/5 + 4/5 = 4/7 + 3/7
5/5 = 7/7
1 = 1

b + 2/5 = 4/7 + 3/7
b + 2/5 = 7/7
b + 2/5 = 1
b = 1 - 2/5
b = 5/5 - 2/5
b = 3/5

3/5 + 2/5 = 4/7 + 3/7
5/5 = 7/7
1 = 1