Rearranging formulae
Maths and statistics discussion, revision, exam and homework help.
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Rearranging formulaeHi, 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. -
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Re: Rearranging formulaeWhen you multiply both sides by 4 the 2V becomes 8V.(Original post by IgorYakov)
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Re: Rearranging formulaeIf you're multiplying through by 4, you have forgotten to do the same with 2V .(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
W = 2V + U/4
4W = 8V + U
4W - U = 8V
(4W - U)/8 = V
which is the same answer given on your image.Last edited by boredom_personified; 08-04-2012 at 15:39. Reason: . -
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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
which is the same answer given on your image.
Aah right damn yeh! :P Sorry
Yeh thanks, just was wondering if all the fractions bit was necessary :P
