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Harder Trinomials - Undoing FOIL

Lock them in:

First: 1 * 4 and Last: 2 * 3 gives ( x + 2 ) ( 4x + 3 ) ... the inner terms give 8x and the outer terms give 3x

So,

4x^2 + 11x + 6 = ( x + 2 ) ( 4x + 3 )

Check with FOIL!

Let's try another one:

Factor  8w^2 - 6w - 9


Possible first guys: 1 * 8 and 2 * 4 , Possible last guys: 1 * 9 and 3 * 3 ... easiest to flip the last guys