What is the square root of -72x?

Step-by-step explanation:

In order to this, you have to find two factors, where one of them is a perfect square, and the other is not, and those numbers are 2 and 36, and since we are dealing with a negative inside the root, it is considered imaginary, or iota. So, we do as follows:

The negative comes out as iota, and since x does not have another x of some sort to pair up with, we leave it inside the radical.

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