The expression 6y^2 - y - 15 can be rewritten as A(y - B)(y - C). Find A + B + C.
Expand A(y - B)(y - C)
A*(y2 - (B+C)y + BC)
Ay2 - A(B+C)y + ABC
Compare the coefficients with those of 6y2 - y - 15
Can you take it from here?
