Question

REALLY NEED HELP WILL GIVE MEDALS FOR CORRECT ANSWER...PLEASE!!!

factor the polynomial using the pattern
X^2+(a+b)x+ab=(x+a)(x+b) that's the pattern
here's the polynomial
x^2+3x-18

Answer 1

@Abhisar do you know/ can you help?
@Brostep0s @Coolsector @Directrix @Donblue22 @CausticSyndicalist @Escobar17 @frizzank @Fazeelayaz @danish071996 @quin100 @TuringTest @KamiBug @kmorgan

Answer 2

https://www.khanacademy.org/math/algebra/multiplying-factoring-expression/factoring-quadratic-expressions/v/factoring-quadratic-expressions

Answer 3

so we have
a+b = 3
a*b=-18

can you find a and b ?

Answer 4

working on it. one moment:) @Coolsector

Answer 5

do you understand how i got those 2 equations ?

Answer 6

okay i thought i did at first because i know i have to have a (a+b) and an (a*b) that equal the same thing, but i am having trouble finding it...

Answer 7

the general form is :
X^2+(a+b)x+ab

and our poly is :
x^2+3x-18

so i look at the terms
you see in our poly 3 is multiplying x
and in the form it is (a+b)
so :
a+b =3

the free term in the form is ab
and in our poly is -18
so
ab = -18

Answer 8

okay so is -18 the final answer? i still don't get what adds & multiplies to get -18...thank you so much for your patience with me!!!

Answer 9

no,
we have two equations :
a+b=3
and ab=-18

i explained how i got them..
are you having trouble solving them ?

Answer 10

yeah...i'm sorry i have such a hard time pin pointing where i'm struggling but i think that would be a great help if you could help me solve them?

Answer 11

sure, but I want you to understand how I got the equations (since it is the first step towards the solution).

so our equations :
a+b=3
ab = -18

we can use the first one and get:
b = 3-a
now plug it into the second one and get:
a(3-a) = -18
a^2-3a-18=0
solving this quad equation give us :
a=6 , -3

plug it into our b=3-a :
b = -3,6

so you can choose
a=6 , b=-3
or the opposite .
in any case you get:

(x-6)(x+3)

Answer 12

so it just all disappeared....on my school:(((( i don't know why but if i get it to reload i'll contact you. CANNOT THANK YOU ENOUGH!!!

Answer 13

ok sure whatever you need