Go step by step to reduce the radical.

Answer:
6√6
Step-by-step explanation:
√(216)
√(4×54)
√(4×(2×27))
√(4×(2×(3×9))
√(2²×(2×(3×3²)) now the 2² and 3² can be pulled out the √
2×3×√(2×3)
6√6 i didn't see that 36×6 = 216
√(216)
√(36×6)
√(6²×6)
6√(6)