If you can't solve by factoring, solve by completing the square.
27. y^2 - 2y = 17
I can't remember how to solve by completing the square. If someone could help with this one, I should be able to remember.
This one can be solved by factoring.
6y^2 - 5y - 4 = 0
(3y - 4)(2y + 1) = 0
Expanding this using FOIL might help you to understand how I factored.
Set each factor to 0 and solve for y.
3y - 4 = 0
3y = 4
y = 4/3
and
2y + 1 = 0
2y = -1
y = - 1/2
Do you understand that?