Question

Pls factorise x²-7x+12

Answer 1

Step-by-step explanation: The first thing you're going to probably

try to do here is to factor out a greatest common factor.

The problem is, there is no factor that is in common

to all three of these terms so you may think it's unfactorable.

However, this trinomial is in a special form.

We have an x squared term, an x term, and a constant term.

When a trinomial is in this form, it can be

factored as the product of two binomials.

So start by setting up two sets of parentheses.

Inside each set, we will have the two terms that compose each binomial.

So we have (    )(    ).

The first term is a factor of the x² term, x · x.

For the second term, we need factors of 12 that add to -7.

Since the middle term is negative, we use the negative factors of 12.

Notice that -4 and -3 add to -7 and multiply to be 12.

So our answer is (x - 4)(x - 3).