Answer:
14√6.
Step-by-step explanation:
√54 = √9√6 = 3√6
√486 = √81 √6 = 9√6.
√24 = √4√6 = 2√6.
So √54 + √486 + √24
= 3√6 + 9√6 + 2√6
= 14√6.