решите систему уравнений спосьбом подстановки
x/3-y/2=-3
x/2+y/5=5

x/3 - y/2 = -3

x/2 + y/5 = 5

x = 3y/2 - 9

3y/4 - 9/2 + y/5 = 5

x = 3y/2 - 9

19y/20 = 19/2

y = 10

x = 6