Question

Factor: 2x2 + 10x - 100

Answer 1

you are trying to get this into 2 polynomials yes?

Answer 2

yes

Answer 3

so you are going to turn this into (2x +/- ?)(x +/- ?)

Answer 4

so the sum of the w ? has to equal 10, but multiply to 100

Answer 5

Factor out the 2 first

Answer 6

2(x+10)(x-100)?

Answer 7

understand?

Answer 8

2(x^2 + 5x - 50)

Answer 9

wait no 2(x-10)(x+10)

Answer 10

That's the factoring short cut, but it's not all the factoring steps.

Answer 11

no no
do you know how to factor x^2 + 5x - 14?

Answer 12

yes yes that is the correct answer, except the 2 will be in the first binomial

Answer 13

@D_ , what you posted was not correct.

Answer 14

i wrote it as 2(x+5)(x-10)
than i got (2x+10)(x-10)
which is now 2x^2-20+10x-100

Answer 15

but the middle part was wrong..

Answer 16

2(x-10)(x+10)? that is correct, it just needs to be (2x-10)(x+10)

Answer 17

2x^2 + 20x - 10x - 100

Answer 18

is what you get when you use foil

Answer 19

2(x^2 + 5x - 50)
2(x^2 + 10x - 5x - 50)
2(x(x + 10) - 5(x + 10))
2((x - 5)(x + 10))
2(x - 5)(x + 10)

Answer 20

that works too

Answer 21

so i just had my signs backwards

Answer 22

@tyler123456789, I don't know if anything you posted was correct.

Answer 23

@D_ what I posted are the proper factoring steps. It's called factor by grouping.

Answer 24

There are other factoring methods, but this one is the most appropriate to use. It is also the most computational and shows the complete set of steps.

Answer 25

ok so now i have to set it equal to zero so it would be x=5, x=-10 ?

Answer 26

I see now. Yes, those are the zeroes.

Answer 27

alrighty now i think i got it , thank you !