Assuming that you want to factor this and find roots, the first thing is to look at the constant
term, -5.

Because is it negative, we immediately know that one factor will have a + sign in the middle and
one will have a - sign in the middle. 5 is a nice constant because it only factors out as 1 x 5.

From this we know that there are only two ways that this can factor conveniently

(ax + 5)(bx - 1) or

(ax - 5)(bx + 1)

To get the rest of it you have to figure out how 12 could be broken down, This is messier because
you have 12 x 1, 3 x 4, 2 x 6 to consider. You have to figure out some combination where
you will get 5a -b or b - 5a to come out to be 28. It will turn out that 5(6) - 2 gets you 28
and it all factors out to be

(2x + 5)(6x - 1)

From this you can get that x = 1/6 and x = -5/2 are roots

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