How do you factor trinomials where the coeffecient a is something other than one?

such as: 6x^2 + x -1 and 2x^2 - 7x + 3 ?

i also have a bit of problem with trigonometry and rather than making a second thread i thought it would be more efficient to just include it in this thread?

Solve each equation for 0 < theta (Θ) < 2 pi (2π)

2sin^2 θ + sin θ - 6 = 0

(1 + 1/tan^2 θ)(1 - sin^2 θ) = 1/tan^2 θ

i hope y'all don't think i'm a dummy, i'm actually doing pretty good in summer school.