#1
well ive got a maths exam that we had to do for homework and i have school in 20 mins lol how do i do this question??? (4x-3y)(2x+y)-(3x-4y)(2x+y) it says to simplify by expanding and collecting like terms.
thanks.
#3
just open up the brackets and then put the Xs on one side and the Ys on the other side.
#6
Wait how doyou have school in 5 minutes
where do you live?
it's like 5:48 PM where i'm at..

on topic
I think luthier did it right
Quote by Twist of fate
So it doesnt feel like scraping your penis on sidewalk



my gear
Ibanez GRX40 guitar
Roland Cube 60 Amp
Ibanez IBZ10G Amp

Member of
[bThe UG Asian Invasion!
Pm night_lights to join the hallowed Asian ranks (Over 2000members)
#7
it has answers but everytime i try and do it i get it rong and the teacher says to sho working and shit and 5x-5y is rong the sheet says answer is 2x(squared) + 3xy + y(squared)
#8
(4x-3y)(2x+y)-(3x-4y)(2x+y)

8x^2 + 4xy - 6xy - 3y^2 - 6x^2 + 3xy - 4xy - 4y^2

8x^2 - 2xy - 3y^2 - 6x^2 - xy - 4y^2

2x^2 - 3xy + y^2

It makes sense to me. But I don't do maths, so I made it up. If I'm right, I invented it.
#9
Well then your answer sheet is wrong. Im doing this in College Algebra and just had a test over it Thursday. The way I did it is correct. Maybe you need to talk to your teacher about it, because their obviously feeding you some wrong shit.
#10
yopu have to use the distributive property of multiplication distribute the 4x to every other x and multiply them together and ten ADD the y's then fit the anser to how many x's you got into where the x is its called substitution
Sex is good
Sex is fine
Doggy Style & 69
Just for fun
Or gettin paid
Everyone likes gettin laid
#11
(4x-3y)(2x+y)-(3x-4y)(2x+y)
Well if you do it by multiplying you get:
4x*2x= 8x
-3y*y= -3y
So the first part would be: 8x-3y

Second part would be:
3x*2x= 6x
-4y*y= -4y
So second is 6x-4y

Whole thing is 8x-3y-6x-4y

So then to combine like terms you would get:
8x-6x= 2x
-3y-4y= -7y

So:
2x-7y

But your answer sheet still is wrong, according to me. So I think your answer sheet is wrong.
#12
Yay! I got it right! I could make it more clear if you don't understand. ^2 = squared, just so you know.
#14
Check your math, his book answer is correct.

Quote by LuthierofTexas
(4x-3y)(2x+y)-(3x-4y)(2x+y)
Well if you do it by multiplying you get:
4x*2x= 8x
-3y*y= -3y
So the first part would be: 8x-3y

Second part would be:
3x*2x= 6x
-4y*y= -4y
So second is 6x-4y

Whole thing is 8x-3y-6x-4y

So then to combine like terms you would get:
8x-6x= 2x
-3y-4y= -7y

So:
2x-7y

But your answer sheet still is wrong, according to me. So I think your answer sheet is wrong.
#16
you FOIL it into *quadratic equation* minues *another quadratic equation*, and then subtract. i dont feel like doing the actual work, but thats how you do it
This is my signature. There are many like it but this one is MINE.
#18
Quote by LuthierofTexas
(4x-3y)(2x+y)-(3x-4y)(2x+y)
Well if you do it by multiplying you get:
4x*2x= 8x
-3y*y= -3y
So the first part would be: 8x-3y

Second part would be:
3x*2x= 6x
-4y*y= -4y
So second is 6x-4y

Whole thing is 8x-3y-6x-4y

So then to combine like terms you would get:
8x-6x= 2x
-3y-4y= -7y

So:
2x-7y

But your answer sheet still is wrong, according to me. So I think your answer sheet is wrong.

You're wrong.

(4x-3y)(2x+y)-(3x-4y)(2x+y)

(4x*2x + 4x*y + -3y*2x + -3y + y) - (3x*2x + 3x*y + -4y*2x + -4y*y)

(8x^2 + 4xy - 6xy - 3y^2) - (6x^2 + 3xy - 8xy - 4y^2)

(8x^2 - 2xy -3y^2) - (6x^2 - 5xy - 4y^2)

8x^2 - 2xy - 3y^2 - 6x^2 + 5xy + 4y^2

8x^2 - 6x^2 - 2xy + 5xy - 3y^2 + 4y^2

2x^2 + 3xy + y^2
#19
Alright. Gibsonpenguin. I can admit when Im wrong. Just seems wierd to me though.

BTW< TS, are you studying physics or something? Cause that shit is ridiculous. You will NEVER need that anywhere other then in a room full of dudes with pocket protectors.
#20
Quote by LuthierofTexas
Alright. Gibsonpenguin. I can admit when Im wrong. Just seems wierd to me though.

BTW< TS, are you studying physics or something? Cause that shit is ridiculous. You will NEVER need that anywhere other then in a room full of dudes with pocket protectors.

Sorry, I didn't mean to sound like an asshole or anything.

No offense or anything, but I learned this stuff in like 10th grade Algebra 2. You were close with what you were doing, but you skipped a couple steps. The way we learned it was called FOIL. Which stands for First, Outer, Inner, Last. So if you are multiplying these two things:

(w + x) * (y + z)

You do the first of each set of parentheses:
wy
Plus the outer amounts:
wz
Plus the inner amounts:
xy
Plus the last amounts of each set of parentheses:
xz

Total:
wy + wz + xy + xz

Then you can combine like terms and simplify (when you're using numbers and less variables). It's also a lot more useful than you seem to think it is.