9у^2-60у+100 0,6у+1 (9y^2-60y+100)(0,6y+1)
___________ * ________=----------------------------------=
9у^2+30у+25 0,6у-2 (9y^2+30y+25)(0,6y-2)
2*(3y-10)(3y-10)(3y+5) 3y-10
------------------------------ =-----------
2*(3y+5)(3y+5)(3y-10) 3y+5
при y=-2/3
3y-10 -2+10
------- = -------- =8/3=2 2/3
3y+5 -2+5