Question

which of the following is a factor or the trinomial below x^2 + x -12 A.(x-3) B. (x+3) C.(x+6) D.(x-4)

Answer 1

What are the two numbers if you multiply them you get 12 and if you add them you get 1. Think about factors of 12

Answer 2

alight where do i go from there ?

Answer 3

Do you know the two numbers or not

Answer 4

two numbers that you get to 12 ?

Answer 5

Yes if you multiply them you get 12

Answer 6

2 and 6 ?

Answer 7

True but those two if you add them you don't get 1. What else

Answer 8

okay you have to add it and get one thats what i wasnt getting

Answer 9

Give me a moment I will open my laptop ok

Answer 10

ok

Answer 11

Alright! know I can Explain to you nicely

Answer 12

(x+a)(x+b)=x^2+(a+b)x+ab. we're doing this factorization

Answer 13

a.b= -12, a+b= 1 do you agree

Answer 14

yes

Answer 15

Good! now what we need to do is to find two number that will give us that -12 and if we add them they give us 1. you sad 2 and 6. let's check

Answer 16

thats not going to work ik already

Answer 17

2x6=12, 2+6= 8, let's check negative case -2x6=-12 , -2 +6=4

Answer 18

yeah i know I'm just going to show you how it works

Answer 19

now let's think about another two numbers that multiply to 12

Answer 20

can you tell me?

Answer 21

cant think of any that would add to one

Answer 22

just for the moment think about any two that multiply to 12 okay
do you know what are the factor of 12?

Answer 23

factor of 12 are the numbers that divide 12? you know this right

Answer 24

yes

Answer 25

{1,2,3,4,6,12} Do you agree that this is the factors of 12?

Answer 26

yeah

Answer 27

we tried 2 and 6, can we try now 3 nd 4?

Answer 28

think about negative sign too not just 3 and 4
it could be -3,4 or -4,3. well actually you need a negative there since we need -12

Answer 29

do you agree

Answer 30

yeah we need to use -3 ,4

Answer 31

ok can you try that if it works?

Answer 32

it does you get one i did it

Answer 33

take your time and do it neatly

Answer 34

Good job!

Answer 35

So now lets put it in this since a=-3 and b=4
we say that (x-3)(x+4)=x^2+x-12 do you agree

Answer 36

that's what we found right?

Answer 37

yep

Answer 38

So x^2+x-12 is factorized to (x-3)(x+4)
can we say the answer to the question is A: (x-3)

Answer 39

because if we multiply (x-3) with (x+4) we get the original trinomial

Answer 40

ohh i get it more than i did thank you

Answer 41

Great job, you did here! you see you can do this. practice more of this and you will master it. And pleasure to help you!

Answer 42

Just follow the same technique, it will always work for you

Answer 43

will do

Answer 44

Okay good!