Question 859994
 {{{sqrt(24) + 5sqrt(6) - sqrt(54)}}}
Factor to reveal a perfect square inside the radical
  {{{sqrt(6*4) + 5sqrt(6) - sqrt(6*9)}}}
Extract the root of those perfect squares
  {{{2sqrt(6) + 5sqrt(6) - 3sqrt(6)}}}
Like terms, just do the math
{{{4sqrt(6)}}}