Factor $6x^2​ −7x−5=0$ I'm trying to factor
$$6x^2​ −7x−5=0$$
but I have no clue about how to do it. I would be able to factor this:
$$x^2-14x+40=0$$
$$a+b=-14$$
$$ab=40$$ 
But $6x^2​ −7x−5=0$ looks like it's not following the rules because of the coefficient of $x$. Any hints?

We can use the AC method, which states that you have to find two factors that multiply up to $ac$ that also add up to $b$. Note that $ac = -30$. There are two factors that satisfy the condition, -10 and 3 (since $-10 + 3 = 3 - 10 = -7$). Now let $u = 3$ and $v = -10$. We can group according to the following form: $$(ax^2 + ux) + (vx + c)$$ When we do that, we get: $$(6x^2 + 3x) + (-10x - 5)$$ Now, you have to note the common factors of each monomial in the binomial. The GCF for $6x^2 + 3x$ is $3x$, hence we can factor that out: $$3x(2x + 1) + (-10x - 5)$$ Also, the GCF of $-10x - 5$ is -5, so we can factor that out: $$3x(2x + 1) - 5(2x+1)$$ The common term here is $2x + 1$, so we factor that out to get: $$(2x + 1)(3x - 5)$$
