How do you simplify -20/(sqrt6 - sqrt2)?

1 Answer
Feb 24, 2016

Rationalize the denominator to find that

-20/(sqrt(6)-sqrt(2))=-5(sqrt(6)+sqrt(2))

Explanation:

We will use the fact that (a-b)(a+b) = a^2-b^2 to rationalize the denominator.

-20/(sqrt(6)-sqrt(2)) = -(20(sqrt(6)+sqrt(2)))/((sqrt(6)-sqrt(2))(sqrt(6)+sqrt(2))

=-(20(sqrt(6)+sqrt(2)))/((sqrt(6))^2-(sqrt(2))^2)

=-(20(sqrt(6)+sqrt(2)))/(6-2)

=-(20(sqrt(6)+sqrt(2)))/4

=-5(sqrt(6)+sqrt(2))