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Well, if each factor had a 5x and each factor had a -4, that would take care of the

and constant terms, so let's see what happens to the middle term:

. Yep, that does it.

. This one has at least one x in every term, so you can start by factoring out an x.

.
Now,

and

, so the rest of this thing should factor to:
Check by multiplying it out:

. Yep, that works.