(2y-5)^2 = (y-3)(6y-15)
4y^2-20y+25=6y^2-33y+45,
4y^2-6y^2-20y+33y+25-45=0,
-2y^2+13y-20=0.
2y^2-13y+20=0,
(y-4)(2y-5)=0,
y1=4,y2=5/2