1. Introduce new variable u = 2x-3. Then your polynomial takes the form 6u^2 - 5u - 4. 2. Then you can factorize the last polynomial 6u^2 - 5u - 4 = (3u-4)*(2u+1). (1) 3. Now substitute back (2x-3) instead of "u" into (1). You will get 6(2x-3)^2-5(2x-3)-4 = (3*(2x-3)-4)*(2*(2x-3)+1) (2) 4. Your next and final step is to simplify (2): 6(2x-3)^2-5(2x-3)-4 = (3*(2x-3)-4)*(2*(2x-3)+1) = (6x-13)*(4x-5). Answer. 6(2x-3)^2-5(2x-3)-4 = (6x-13)*(4x-5).