If you would like to find the difference (6y^3 + 17y - 3) - (4y^3 - 11y + 9), you can do this using the following steps:
(6y^3 + 17y - 3) - (4y^3 - 11y + 9) = 6y^3 + 17y - 3 - 4y^3 + 11y - 9 = 2y^3 + 28y - 12
The correct result would be 2y^3 + 28y - 12.