The procedure is: 

1. Put parentheses around the denominator:
2. Create the conjugate of the denominator and put it in parentheses
3. Put that conjugate over itself (which has value 1)
4. Multiply by that.  (multiplying it won't affect the value since it equals 1)

1. Put denominator in parentheses: 

2. To create the conjugate of , just change the
   sign of the second term, making the conjugate .
   Put it in parentheses .
3. Put that conjugate over itself, like this 
4. Multiply by that:






FOIL out the bottom:



The two middle terms cancel out on the bottom:





On the bottom,  is just 5 and  is just 3







Divide top and bottom by 2



Edwin