Answer:
The path is 17 ft long.
Explanation:
Let c represent the length of the hypotenuse of a right triangle, and let a and b represent the lengths of its legs, as pictured in the image below.
The relationship involving the legs and hypotenuse of the right triangle, given by

is called the Pythagorean Theorem.
The diagonal of the rectangle is equivalent to finding the length of the hypotenuse of a right triangle with sides 8 feet wide and 15 feet long.
Applying the Pythagoras' Theorem, we get

Technically, there are two answers to
, i.e., d = 17 or d = -17. However, d represents the hypotenuse of the right triangle and must be non-negative. Hence, we must choose d = 17.
The path is 17 ft long.