Answer:
23.4 ft
Step-by-step explanation:
The straight-line distance (d) from the top of the pole to the attach point on the ground is given by the Pythagorean theorem:
d² = 15² +18² = 549
d = √549 = 3√61 ≈ 23.4 . . . . feet
The wire is about 23.4 feet long.
