Question

Помогите с 4 и 5 очень надо 

Answer 1

x/7+x/8+x=-48/7
8x/56+7x/56+56x/56=-48/7
71x/56=-48/7
71x=-48/7*56/1
71x=-2688/7
x=-2688/7*1/71
x=-2688/497
x=-384/71=-5 29/71

y/4+y/5+y=-26/5
5y/20+4y/20+20y/20=-104/20
29y/20=-104/20
29y=-104
y=-104/29
y=-3 17/29