SOLUTION: Please help me solve this: 1/a+1/b=c for b

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Question 132939: Please help me solve this:
1/a+1/b=c for b
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
1%2Fa+%2B+1%2Fb+=+c
multiply both sides by b
b%2Fa+%2B+1+=+bc
Subtract bc from both sides
b%2Fa+-+bc+%2B+1+=+0
Subtract 1 from both sides
b%2Fa+-+bc+=+-1
Factor out b from left side
b%281%2Fa+-+c%29+=+-1
Divide both sides by 1%2Fa+-+c
b+=+%28-1%29+%2F+%281%2Fa+-+c%29
To simplify the right side, multiply
the right side by %28-a%29%2F%28-a%29, which is 1,
so nothing is really changed
b+=+a+%2F+%28ac+-+1%29 answer
check answer:
1%2Fa+%2B+1%2Fb+=+c
What is 1%2Fb?
1%2Fb+=+%28ac+-+1%29+%2F+a (from the answer)
1%2Fa+%2B+%28ac-1%29%2Fa+=+c
Multiply both sides by a
1+%2B+ac+-+1+=+ac
ac+=+ac
OK