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# Rearranging formulae Tweet

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1. Rearranging formulae
Hi, i was doing some practice on this and there was a question: to amke V the subject

W = 2V + U

now the final answer off the tutorial was:

However i was wondering, could you do

W = 2V + U

then multiply both sides by 4 (or divide by 0.25)

so you get

4W = 2V + U
4W-U = 2V

then

= V

:O?
Last edited by IgorYakov; 08-04-2012 at 15:34.
2. Re: Rearranging formulae
DAMN! Wait sorry! Let me edit that

Sorry i wrote it wrong, corrected now
Last edited by IgorYakov; 08-04-2012 at 15:36.
3. Re: Rearranging formulae
(Original post by IgorYakov)
-
When you multiply both sides by 4 the 2V becomes 8V.
4. Re: Rearranging formulae
(Original post by IgorYakov)

However i was wondering, could you do

W = 2V + U

then multiply both sides by 4 (or divide by 0.25)

so you get

4W = 2V + U
4W-U = 2V

then

= V
If you're multiplying through by 4, you have forgotten to do the same with 2V .

W = 2V + U/4
4W = 8V + U

4W - U = 8V

(4W - U)/8 = V
Last edited by boredom_personified; 08-04-2012 at 15:39. Reason: .
5. Re: Rearranging formulae
(Original post by boredom_personified)
If you're multiplying through by 4, you have forgotten to do the same with 2V .

W = 2V + U/4
4W = 8V + U

4W - U = 8V

(4W - U)/8 = V

Aah right damn yeh! :P Sorry

Yeh thanks, just was wondering if all the fractions bit was necessary :P