
Donald W. answered 03/18/22
Experienced and Patient Tutor for Math and Computer Science
We should start by defining our f(x), which will represent the total amount of cabling required for some central point (x,0):
f(x) = 2√(x2 + 9) + 8 - x
Here, x2 + 9 is the distance from the central point to either Springfield or Shelbyville and 8 - x is the distance from the central point to Centerville.
To find the critical points, you would take the derivative of f(x) and find values of x that make f'(x) equal to 0. Can you do the rest of the problem yourself?