SOLUTION: This is a question about rationalizing a binomial denominator. I am not sure how to get the -r out of the final equation without turning the 9 into a negative number also by simpl

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Question 257216: This is a question about rationalizing a binomial denominator. I am not sure how to get the -r out of the final equation without turning the 9 into a negative number also by simply multiplying both numerator and denominator by
-1. Anyway, here is the problem I am trying to solve.
+sqrt+%28r%29+ over 3 -+sqrt+%28r%29+
The answer I come up with is 3 +sqrt+%28r%29+ +r over 9-r.
Found 2 solutions by ankor@dixie-net.com, drk:
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
This is a question about rationalizing a binomial denominator. I am not sure how to get the -r out of the final equation without turning the 9 into a negative number also by simply multiplying both numerator and denominator by
-1. Anyway, here is the problem I am trying to solve.
+sqrt+%28r%29+ over 3 -+sqrt+%28r%29+
The answer I come up with is 3 +sqrt+%28r%29+ +r over 9-r.
:
But that's right, you got rid of the radical in the denominator, that's all you can do

Answer by drk(1908) About Me  (Show Source):
You can put this solution on YOUR website!
The original problem was
sqrt%28r%29%2F%283-sqrt%28r%29%29
step 1 - rationalize the denominator to get
sqrt%28r%29%2A%283%2Bsqrt%28r%29%29 / %28%283-sqrt%28r%29%29%2A%283%2Bsqrt%28r%29%29%29
step 2 - distribute top and bottom to get
%283sqrt%28r%29%2Br%29 / 9-r
This is your answer