You can
put this solution on YOUR website!Rationalise the denominator:

=

To "rationalise" the denominator means to remove the radical sign and this can be done here by multiplying the numerator and the denominator by

.

Substitute

Perform the indicated multiplication in the numerator.

Rewrite

Take the square root of 16 (that's 4) and move it outside the radical.

Rewrite

Cancel the 4's

or