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

User Plesiv
by
5.0k points

2 Answers

1 vote

Answer:

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

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!!

User Johnnymatthews
by
5.3k points
5 votes
the answer to this is (x-10) (x+4)
User Pero
by
5.4k points
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