SOLUTION: Rationalize the denominator. Assume that all variables represent positive real numbers and that the denominator is not zero. 7 ____ 9- (3 under a radical) So it's 7 divi

Algebra ->  Radicals -> SOLUTION: Rationalize the denominator. Assume that all variables represent positive real numbers and that the denominator is not zero. 7 ____ 9- (3 under a radical) So it's 7 divi      Log On


   

Question 292392: Rationalize the denominator. Assume that all variables represent positive real numbers and that the denominator is not zero.
7
____
9- (3 under a radical)

So it's 7 divided by 9 minus the square root of 3.
I think. I'm trying to write this so it makes sense.
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


Here's how to write it so it makes sense:

7/(9-sqrt(3))

Anyone can read that to mean



First review my lesson on Rationalizing Denominators: http://www.algebra.com/algebra/homework/Radicals/rationalizingdenominators1.lesson

Then you need the conjugate of the denominator. If you have a binomial expression, such as , then its conjugate is

So the conjugate of your denominator is

Now multiply your expression by 1 in the form of the conjugate divided by itself.



Remember that the product of a binomial and its conjugate is the difference of two squares:



Yes, it's ugly, but at least there is no radical in the denominator.

John