Tìm y ∈ Q, biết: y : (2/9 - 1/5) = 8/16

Tìm y ∈ Q, biết :
a| y :(2/9 - 1/5)= 8/16
b| 4- 3y
_________ = 0
2y+5
c| (y-2) x (y+ 2/3) > 0