Question

Which expression is the factored equivalent of x2 - 7x + 12?

Answer 1

A very good way to remember how to factor for something like this is using the technique:

__________ x^2

ADDS TO 7

MULITPLIES TO 12

So, clearly, we can see that 4 & 3 add to 7 and multiply to 12. When you take into account the negative sign in front of the 7, we get:

x^2 - 7x + 12 = (x-4)(x-3)

-4 + -3 = -7

-4 * -3 = +12