SOLUTION: Please help me solve this equation: 1/R = 1/r^1 + 1/r^2 for r^2

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Question 50623This question is from textbook Algebra 2
: Please help me solve this equation: 1/R = 1/r^1 + 1/r^2 for r^2 This question is from textbook Algebra 2

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
1/R = 1/r^1 + 1/r^2 for r^2
Multiply thru by Rr^2 to get:
r^2 = rR + R
r^2-Rr-R=0
You have a quadratic in "r":

r=[R+-sqrt(R^2+4R)]/2
Cheers,
Stan H.