Expanding the expressions:

(у-8)(2y-1) = 2y^2 - y - 16y + 8 = 2y^2 - 17y + 8

(3y+1)(5y-2) = 15y^2 - 6y + 5y - 2 = 15y^2 - y - 2

Now, we subtract the second expression from the first:

(у-8)(2y-1)-(3y+1)(5y-2) = (2y^2 - 17y + 8) - (15y^2 - y - 2)
= 2y^2 - 17y + 8 - 15y^2 + y + 2
= -13y^2 - 16y + 10

So, (у-8)(2y-1)-(3y+1)(5y-2) simplifies to -13y^2 - 16y + 10.