Final answer:
The expression 6√x can be evaluated as 6 times the square root of x, so the correct answer is 6x.
Step-by-step explanation:
The expression 6√x can be evaluated as 6 times the square root of x. So the correct answer is (a) 6x. To understand this, let's take an example. Suppose x = 9, then 6√x = 6√9 = 6 * 3 = 18. Therefore, the expression 6√x simplifies to 6x.