Question

Help! Factor the expressions. x2 + 6x − 40 =

Answer 1

The answer to this is (x-10) (x+4)

Answer 2

Answer:

Your answer would be (x - 4)(x + 10)

Step-by-step explanation:

$x^{2}$ + 6x - 40 =

So you first figure out what times what equals 1 (because there is a one in front of the $x^{2}$) That is just x.

(x ? ?)(x ? ?)

Next, you move onto the -40. Figure out what times what equals 40. These two numbers that you multiple then need to be added to make the middle number, which, in this case, is 6.

So 5 times -8 would be out of the picture because 8 - 5 is not 6.

-4 times 10 equals -40

So then you need to figure out WHERE you plug these in.

It would look like (x - 4)(x + 10)

It would NOT be (x - 10)(x + 4) because 4 plus -10 is -6, and we need a positive 6.

You can then check your answer by factoring, which would give you $x^{2}$ + 10x - 4x -40, simplify, and now you have $x^{2}$ + 6x - 40.

Sorry if that was wayyyy too confusing!!