# Algebra

posted by .

Solve the equation w=Cr^-2 for r.

This is what I got so far....

w/C=r^-2

Then I think it's...

ok so I don't really know. I want to put w/C=1/r^2 but the r is still not alone and I'm not sure where I'd take it from there. Please help.

• Algebra -

W = Cr^-2
W = C * 1/r^2
Multiply both sides by r^2
r^2 W = C
r^2 = C/W

• Algebra -

I think your right. I got the same thing but for some reason I thought that the r is still not alone. Are you sure i don't go one step further and say that

r=sqrt(c/w)

what do you think?

• Algebra -

Sorry, I forgot the last step.

r = +- (sqrt(C/W))

• Algebra -

Thanks. one more question. Why did you do the +- thing?

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