Ok so this one can be factored like this first:
3(6x^2-5x-6)
Then you have to factor like you normally would for a complex one:
(Put aside the 3 for now just know it's there to make the problem easier)
6x^2-9x+4x-6
3x(2x-3)+2(2x-3)
Adding the 3 put aside now
3(3x+2)(2x-3) is the final factored answer