Answer: 
This is the same as saying 18*sqrt(2) or you could say 18√2
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Explanation:
We'll be using this square root rule: 
So we could have this as our steps:

Therefore, 
The basic idea is to first combine the roots using that rule. From there, we factor the radicand such that we pull out the largest perfect square factor. This will allow us to break the root apart and fully simplify it.
The question is asking to write and equation by using the two variable in the standard form that ca be used to describe the velocity of thecar at different times and base on my calculation, I would say that the answer would be v=4t+39. I hope you are satisfied with my answer and feel free to ask for more