@mathmale Hello, When dividing and rationalizing denominators, if the bottom is already a positive do you still need to times both by the denominators opposite?

Question

@mathmale  Hello, When dividing and rationalizing denominators, if the bottom is already a positive do you still need to times both by the denominators opposite?

mathmale · Answer

Hello, Nicole!
I'd appreciate your sharing a couple of the math problems you're working with, because that 'd make it easier to come up with suitable responses.
MM

nicole143 · Answer

No problem, here is what I'm working with. 
P.s. Did you get my message?

nicole143 · Answer

I haven't done anything yet because I don't know wether or not to time both top and bottom by 1 + square root 18. @mathmale

nikato · Answer

for that problem^ u would actually have to multiply 1- sqrt 18 top and bottom

nikato · Answer

so
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