Answer:
The end points of line segment are:

Using distance formula,
Distance =
= 
Edited : I apologise I misunderstood the question.
You can solve the equation.
C is the answer to the problem
Divide 83.524 by pi then take half of that answer .
the answer should be 13.29 or 13.3
4.5X+1450=C
X represents the amount of square feet
C represents the total cost