Question

Factor:
4x2 - 9y2

Answer 1

okay use this formula:
a^2-b^2=(a-b)(a+b)

Answer 2

ur a=2x, b=3y

Answer 3

difference of 2 squares

Answer 4

This is a difference of squares: A^2-B^2=(A+B)(A-B)

In this case, A=2x and B=3y


So 4x^2-9y^2=(2x+3y)(2x-3y)

Answer 5

Plug that in and get the answer, this is simple, you can doit yourself

Answer 6

and jim, guide them but don't post the answers, i think they should do it themselves.

Answer 7

What I mean is tell them what to do.

Answer 8

i really wish i understood all of this lol

Answer 9

true, but I find it helps to step them through it

Answer 10

sarsar56, you will need this in your future life.

Answer 11

it weill be (2x+3y)(2x-3y)

Answer 12

if not sarsar, let me know

Answer 13

9x^2+16 so how would id o this one

Answer 14

Well jim we already factored a couple of problems. Like see what i mean, tell them to use this formula:
a^2-b^2 = (a-b)(a+b)
Tell them to observe that:
4x2 - 9y2 = (2x)^2-(3y)^2, and tell them to do the substitution to factor.

Answer 15

Sarsar I don't think that's factorable.

Answer 16

Wait we can complete the square

Answer 17

you can complete the square, but that won't make it factorable

Answer 18

how do u know if something is not factorablw

Answer 19

thi will be like this (3x+4)(3x-4)

Answer 20

I think it can be factored

Answer 21

if you have a sum of squares, then it is NOT factorable.

Answer 22

whats a sum of squares

Answer 23

9x^2+16
(3x)^2 + 2*3x*4 + 4^2 - 2*3x*4

Answer 24

(3x+4)^2-24x

Answer 25

a square is any expression that can be represented by squaring another expression.

For example, 4 is a square of 2 since 2 squared = 4

Also, 4x^2 = (2x)^2 is another square

Answer 26

ouch i am sorry i thought there is minuse so sorry!!!

Answer 27

And then:
(3x+4-sqrt(24x))(3x+4+sqrt(24x))

Answer 28

I mean that just makes it uglier haha

Answer 29

but when they say "factorable", they mean over the rationals.

Answer 30

and you forgot the imaginary terms, which makes it even worse

Answer 31

oh i guess, i mean i never learned how u guys do it here in the US.

Answer 32

i kind of see it but not really ):

Answer 33

don't worry about it, 9x^2+16 is NOT factorable

Answer 34

how about this one 2xy-xz+2wy-wz

Answer 35

Okay sarsar observe what is similar in the equation

Answer 36

which would b the 2y?

Answer 37

2xy-xz+2wy-wz
2xy+2wy-xz-wz
2y(x+w)-z(x+w)

Answer 38

So:
(x+w)(2y-z)

Answer 39

i think u can do like this : 9x^2 +9+7
then we wil factor : 9(x^2+1)+7
then:( 9+7)(x^2+1)

Answer 40

am i right?

Answer 41

4ax + 8ay + 3bx + 6by
so like in this one, do i start by taking out the GCF?

Answer 42

sorry Roh, that's not the correct factorization. You can verify that by expanding

Answer 43

no u pulled out 9+7, u can't do that

Answer 44

first, group terms

(4ax + 8ay) + (3bx + 6by)

Answer 45

what comes next?

Answer 46

mmmm yeah ur right bahroom

Answer 47

Jim where did u get that one from?

Answer 48

which one?

Answer 49

oh u just took it as an example? I see
was talkin about this (4ax + 8ay) + (3bx + 6by)

Answer 50

ahhhhh im confused lol

Answer 51

I think ima leave, having too much people to help confuses others

Answer 52

*too many

Answer 53

yoou can factor it by group factoring sarsar no confusing is needed let me do it

Answer 54

4ax + 8ay + 3bx + 6by

(4ax + 8ay) + (3bx + 6by)

4a(x + 2y) + 3b(x + 2y)

(4a+3b)(x + 2y)

Answer 55

4ax + 8ay + 3bx + 6by
ok so u group the terms
(4ax+8ay) (3bx+6by)

Answer 56

first group the terms, then pull out the GCF from each group. From there, combine like terms.

Answer 57

4a(x+2y)+3b(x+2y)
(x+2y)(4a+3b)