SOLUTION: Hello- My name is Jessica and I am a tutor too. I could not get these for my student. Please help and explain so I can help him. Thank you!! 1. 1/p-1/q= 1/f solve for f

Algebra ->  Expressions-with-variables -> SOLUTION: Hello- My name is Jessica and I am a tutor too. I could not get these for my student. Please help and explain so I can help him. Thank you!! 1. 1/p-1/q= 1/f solve for f      Log On


   

Question 104508: Hello-
My name is Jessica and I am a tutor too. I could not get these for my student. Please help and explain so I can help him.
Thank you!!

1. 1/p-1/q= 1/f solve for f

2. A= (h(a+b))/2 solve for b
3. V= Q/r1- Q/R2 solve for Q
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Ok Jessica, here we go:
1. 1%2Fp+-+1%2Fq+=+1%2Ff It will simplify things a bit if we first subtract the fractions on the left side.
%28q-p%29%2Fpq+=+1%2Ff Now multiply both sides by f.
f%28%28q-p%29%2Fpq%29+=+1 Now multiply both sides by the inverse of %28%28q-p%29%2Fpq%29. This is the same as dividing both sides by %28%28q-p%29%2Fpq%29
f+=+%28pq%2F%28q-p%29%29
2. A+=+%28h%28a%2Bb%29%29%2F2 Solve for b. First, multiply both sides by 2.
2A+=+h%28a%2Bb%29 Now divide both sides by h.
2A%2Fh+=+a%2Bb Finally, subtract a from both sides.
%282A%2Fh%29-a+=+b
3. V+=+%28Q%2Fr%5B1%5D%29-%28Q%2FR%5B2%5D%29 Solve for Q (I hope I interpreted this correctly!) First, factor the Q.
V+=+Q%28%281%2Fr%5B1%5D%29-%281%2FR%5B2%5D%29%29 Simplify the right side.
V+=+Q%28%28R%5B2%5D-r%5B1%5D%29%2Fr%5B1%5DR%5B2%5D%29 Now multiply both sides by the inverse of %28%28R%5B2%5D-r%5B1%5D%29%2Fr%5B1%5DR%5B2%5D%29
V%28r%5B1%5DR%5B2%5D%2F%28R%5B2%5D-r%5B1%5D%29%29+=+Q
Done!