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Rearranging Help

if you were to have as an example: C=2(x+a)

If the answer is C-2a/2

Why can this not be written as C/2-a
Reply 1
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B_9710
18
Original post by JackLeggett
if you were to have as an example: C=2(x+a)

If the answer is C-2a/2

Why can this not be written as C/2-a


It can be written that way. They are exactly the same.
Original post by JackLeggett
if you were to have as an example: C=2(x+a)

If the answer is C-2a/2

Why can this not be written as C/2-a


They can but writing it as C-2a/2 is clearer so preferred
Original post by JackLeggett
if you were to have as an example: C=2(x+a)

If the answer is C-2a/2

Why can this not be written as C/2-a


C−2a2=C2−2a2=C2−a\displaystyle \frac{C-2a}{2}=\frac{C}{2}-\frac{2a}{2}=\frac{C}{2}-a
same ting
Reply 5
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JackLeggett
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9
Original post by abc_123_
They can but writing it as C-2a/2 is clearer so preferred


Thanks for help. When the equation is C=2 √h(2x-h). ( √h(2x-h) is all rooted) I have got it down to c^2/4=h(2x-h), where do I go from here?
Reply 6
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B_9710
18
Original post by JackLeggett
Thanks for help. When the equation is C=2 √h(2x-h). ( √h(2x-h) is all rooted) I have got it down to c^2/4=h(2x-h), where do I go from here?


What are you trying to do?
Reply 7
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JackLeggett
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9
Original post by B_9710
What are you trying to do?


Sorry, make x the subject, I have c^2/2h+h/2=x is this correct
(edited 7 years ago)
Original post by JackLeggett
Thanks for help. When the equation is C=2 √h(2x-h). ( √h(2x-h) is all rooted) I have got it down to c^2/4=h(2x-h), where do I go from here?


Can u Write down the whole equation please xx :smile:
Reply 9
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JackLeggett
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9
Original post by abc_123_
Can u Write down the whole equation please xx :smile:




I have solved it to



is this correct??
Original post by JackLeggett


I have solved it to



is this correct??


Nope. What happens to the 2 in front of the root when you square both sides? You seemed to have ignored it completely.
Original post by JackLeggett


I have solved it to



is this correct??


I think that's right x
(edited 7 years ago)
Original post by abc_123_
Yea that's right xx
Well done :smile:


Nope.
Original post by RDKGames
Nope.


What?
I got two answers:
First attempt = c^2 / 8h
2nd attempt = c^2 / 2h
(edited 7 years ago)
Original post by abc_123_
What?


It's incorrect and you said it's correct.
Original post by RDKGames
It's incorrect and you said it's correct.


I thought it was … sorry
Original post by RDKGames
Nope. What happens to the 2 in front of the root when you square both sides? You seemed to have ignored it completely.


?? I divided C by the 2 in front of the root?? Also I posted this question on another thread with the same answer and you said it was correct, I am not being rude I am just confused??
Original post by JackLeggett
?? I divided C by the 2 in front of the root?? Also I posted this question on another thread with the same answer and you said it was correct, I am not being rude I am just confused??


I said it was correct because you the way you wrote the question made me miss out on the 2 as it was so close to the equals sign while the rest of the equation was separated by a space hence I ignored it so your answer was correct in that case. I edited that comment soon after I saw your post here and noticed the 2 in front.

Okay so you divide by 2, still didn't get the right answer as you didn't square LHS properly.
Reply 18
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B_9710
18
Original post by JackLeggett
?? I divided C by the 2 in front of the root?? Also I posted this question on another thread with the same answer and you said it was correct, I am not being rude I am just confused??


Correct answer is x=c2+4h28h x=\frac{c^2+4h^2}{8h} , of course there are alternative forms that are equivalent to this.
Original post by RDKGames
I said it was correct because you the way you wrote the question made me miss out on the 2 as it was so close to the equals sign while the rest of the equation was separated by a space hence I ignored it so your answer was correct in that case. I edited that comment soon after I saw your post here and noticed the 2 in front.

Okay so you divide by 2, still didn't get the right answer as you didn't square LHS properly.


Oh Ok thanks

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