I have an equation that is a = d/b + d/c . Supposedly this means that
d = a / (1/b + 1/c) is also true. How do you get from the first equation to the second?
Someone told me to factor out d first but I'm not sure how. Thanks.
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if [a = d/b + d/c] then [d = a / (1/b + 1/c)] 
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if [a = d/b + d/c] then [d = a / (1/b + 1/c)]
by gcmky on Mon May 23, 2011 8:39 pm
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by stapel_eliz on Mon May 23, 2011 10:48 pm
gcmky wrote:I have an equation that is a = d/b + d/c . Supposedly this means that
d = a / (1/b + 1/c) is also true. How do you get from the first equation to the second?
Someone told me to factor out d first but I'm not sure how. Thanks.
If you had "db + dc", would you be able to factor?
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stapel_eliz - Posts: 1705
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Re:
by gcmky on Mon May 23, 2011 11:20 pm
stapel_eliz wrote:gcmky wrote:I have an equation that is a = d/b + d/c . Supposedly this means that
d = a / (1/b + 1/c) is also true. How do you get from the first equation to the second?
Someone told me to factor out d first but I'm not sure how. Thanks.
If you had "db + dc", would you be able to factor?
Think I got it. Thanks.
a = d/b + d/c
a = d(1/b) + d(1/c)
a = d(1/b + 1/c)
a/(1/b + 1/c) = d(1/b + 1/c) / (1/b + 1/c)
a/(1/b + 1/c) = d
- gcmky
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by stapel_eliz on Mon May 23, 2011 11:29 pm
gcmky wrote:Think I got it. Thanks.
a = d/b + d/c
a = d(1/b) + d(1/c)
a = d(1/b + 1/c)
a/(1/b + 1/c) = d(1/b + 1/c) / (1/b + 1/c)
a/(1/b + 1/c) = d
Exactly! Good work!
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stapel_eliz - Posts: 1705
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