(3y-5)/7=(2y+4)/5-2

5(3y-5)=7(2y+4)-70

5(3y-5)-7(2y+4)+70=0

15y-25-14y-28+70=0

y=17

(3y-5)/7=(2y+4)/5-2 

(3у-5)/7= (2у+4)/5-(2*5)/5

(3у-5)/7=(2у+4)-10/5

5(3у-5)=7(2у+4)-7*10

15у-25-14у-28+70=0

у=17