Question 1062430

hey,
I need help on rationalizing a denominator. 

the question is 5/root 10.
I know I need to multiply both top and bottom my root 10. when I do that, i get 5 root 10/10. the computer says it's wrong. can you help me?
<pre>You're not done yet, since {{{5sqrt(10)/10}}} can be reduced to: {{{highlight_green(matrix(1,3, cross(5)sqrt(10)/2cross(10), "=", sqrt(10)/2))}}}