SOLUTION: How do I solve the following equation for "f"? a=(2pirf)^2/r This is how far I got: a=4pi^2r^2f^2/r a=4pi^2rf^2 a/4pi^2r=f^2 If this is correct so far, where do I

Algebra ->  Expressions-with-variables -> SOLUTION: How do I solve the following equation for "f"? a=(2pirf)^2/r This is how far I got: a=4pi^2r^2f^2/r a=4pi^2rf^2 a/4pi^2r=f^2 If this is correct so far, where do I      Log On


   



Question 71201: How do I solve the following equation for "f"?
a=(2pirf)^2/r
This is how far I got:
a=4pi^2r^2f^2/r
a=4pi^2rf^2
a/4pi^2r=f^2
If this is correct so far, where do I go from here?

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
a=(2pirf)^2/r
:
This is how far I got:
a=4pi^2r^2f^2/r
a=4pi^2rf^2
:
At this point just divide both sides by 4*pi^2*f^2 which leaves you with
a%2F%284%2Api%5E2%2Af%5E2%29 = r
:
you could also write it:
r = a%2F%282pi%2Af%29%5E2
:
Student pointed out to me that I should have solved for f not r:
a = %284%2Api%5E2%2Ar%2Af%5E2%29
:
Divide both sides by (4*pi^2*r) and you have:
a%2F%284%2Api%5E2%2Ar%29 = f^2
:
f = sqrt%28a%2F%284%2Api%5E2%2Ar%29%29
:
You can also write it:
f = %281%2F%282pi%29%29+%2A+sqrt%28a%2Fr%29