Answer :
Given :
Everyday Isabel swims 10-20 laps in a 50 meter pool.
The amount of time she spends swimming is represented by the function f(x) = 3x .
To Find :
The speed of Isabel.
Solution :
Distance travelled in x laps is, D = 50x .
It is given that time taken is, t = 3x .
So, speed of Isabel is given as :
[tex]Speed=\dfrac{Distance}{Time}\\\\Speed = \dfrac{50x}{3x}\\\\Speed = \dfrac{50}{3}=16.67 \ m/s[/tex]
Hence, this is the required solution.