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Rearrange 5y-3x-4=0 to get y=mx+c? Help please

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Original post by Naruke
this is gcse maybe even KS3


That's what you think
Reply 21
Original post by Pinkberry_y
That's what you think


lmao
Original post by vector12
Thank you. I wasn't sure what happened to the 0, but it seems that once you move the -4 to the other side and it becomes +4 to cancel it out, that then makes the 0 disappear from the equation and gets rid of it?

So basically, the 0 is gotten rid of once you move one of the subjects to the right side of the equation, and it is just a placeholder after the = sign?


You're welcome!
Yeah you can think of it in a way of 'zeroing' a unit on a side so when you add 4

5y - 3x - 4 = 0
(+4) 5y - 3x -4 + 4 = 0 + 4 (+4)
obviously 4-4 = 0. So it essentially 'zeroes' it on the y side - you do this till you get the y on it's own.
Original post by Pinkberry_y
That's what you think


It is.
Original post by vector12
How do you do it? I can do it normally, just I cannot rearrange it with the 0.

Can someone also explain to me what the 0 does please, and if it means anything?

Thanks!
Add 3x to the right hand side and left hand side. Add 4 to the right hand side and left hand side.

You should end up with 5y=3x+4. because the 3x's and 4's subtract and give zero on the left hand side and the 3x and 4 add to the zero on the right hand side.

Divide everything by 5.

You should end up with y=3/5x + 4/5.

Makes sense?
(edited 7 years ago)
where does it say that?

Original post by RDKGames
Whether you agree with me or not is irrelevant. Posting full solutions on this forum is against its rules. Just hint the OP in the right direction next time.
Original post by zainyyyyy
where does it say that?


Sticky at the top of the forum. The one you're supposed to read before posting.

http://www.thestudentroom.co.uk/showthread.php?t=4066671&p=64637319#post64637319
Reply 27
Original post by zainyyyyy
where does it say that?


http://www.thestudentroom.co.uk/showthread.php?t=4066671&p=64637319#post64637319

I'm guessing you didn't read the big red "Please Read - Posting Guide" thing at the top of the page...?
Original post by Pinkberry_y
Y = 3/5x +20


BTW it's against the rules to just give the answer. Also, I would guess that it's super against the rules to give the wrong answer.
Reply 29
Original post by anosmianAcrimony
BTW it's against the rules to just give the answer. Also, I would guess that it's super against the rules to give the wrong answer.


hahahhahahahhahaha
Original post by anosmianAcrimony
BTW it's against the rules to just give the answer. Also, I would guess that it's super against the rules to give the wrong answer.


Original post by Naruke
hahahhahahahhahaha


Can someone tell me how my answer is wrong seeing as this is a learning process for all.
FYI I meant 3x/5
Reply 31
Original post by Pinkberry_y
Can someone tell me how my answer is wrong seeing as this is a learning process for all.
FYI I meant 3x/5


So you want me to teach you?
Original post by Pinkberry_y
Can someone tell me how my answer is wrong seeing as this is a learning process for all.
FYI I meant 3x/5


3x/5 is correct, but 4/5 is not 20.
Well y=mx+c=mx+c+0y = mx+c = mx + c+ 0, but 0=5y3x40=5y-3x-4, so, substituting, y=mx+c+5y3x4y = mx+c+5y-3x-4.
The rest is easy.
Original post by EricPiphany
Well y=mx+c=mx+c+0y = mx+c = mx + c+ 0, but 0=5y3x40=5y-3x-4, so, substituting, y=mx+c+5y3x4y = mx+c+5y-3x-4.
The rest is easy.


Er, no.

That would get him y=14(3m)x+14(4c)y=\frac{1}{4}(3-m)x+\frac{1}{4}(4-c) which is not what we want.
Original post by RDKGames
3x/5 is correct, but 4/5 is not 20.

Ohhhhh OMG I multiplied by accident.
Original post by Naruke
So you want me to teach you?


See I did know what I was doing
Original post by RDKGames
Er, no.

That would get him y=14(3m)x+14(4c)y=\frac{1}{4}(3-m)x+\frac{1}{4}(4-c) which is not what we want.


But you forget that 5y3x4=05y-3x-4 = 0.
Reply 37
Original post by Pinkberry_y
Ohhhhh OMG I multiplied by accident.


See I did know what I was doing


if you say so bae
Reply 38
Original post by RDKGames
Er, no.

That would get him y=14(3m)x+14(4c)y=\frac{1}{4}(3-m)x+\frac{1}{4}(4-c) which is not what we want.


It was a joke. :tongue:
(edited 7 years ago)
Original post by Zacken
It was a joke. :tongue:


Of course :smile:

Spoiler

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