Question

y-(52-13)=17, 28+34+a=100​

Answer 1

у-(52-13)=17
у-39=17
у=17+39
у=56
проверяем:
56-(52-13)=17
56-39=17
17=17

28+34+а=100
62+а=100
а=100-62
а=38
проверяем:
28+34+38=100
62+38=100
100=100

Answer 2

у-(52-13)=17
у-39=17
у=17+39
у=56
56-(52-13)=17

Answer 3

2?