Which of the following is a radical equation?

D)

Step-by-step explanation:

If x is under a radical symbol, then it is called radical equation.

For example,

From the given equations, we have to find in which equation x under radical.

x + , here x is not under radical.

,  here also x is not under radical.

3 + x√7 =13, here x is not under radical

7

Here x is under the radical symbol.

Therefore, the answer is

rowboat a = 160/40 =4 meters per second

rowboat b = 150/50 = 3 meters per second

rowboat c = 180/30 = 6 meters per second

rowboat d = 100/20 = 5 meters per second

rowboat c was the fastest