To "rationalize the denominator" is another way to say, getting rid of that pesky radical at the bottom.
we'll simply start by multiplying top and bottom by the "conjugate" of the denominator, recall difference of squares, anyhow, let's do so
O is the property for the question.
Use the PEMDAS method
-solve equation in parentheses
-solve exponents
-solve multiplication
-solve division
-solve addition then subtract