Answer:
A. 12.5 ft
Explanation:
The geometry is modeled by a right triangle with legs 6 ft and 11 ft. The length of the rope is the length of the hypotenuse of that triangle. That is given by the Pythagorean theorem:
c² = a² +b² . . . . . . where c is the hypotenuse and a, b are the leg lengths
c = √(a² +b²) = √(6² +11²) = √(36 +121) = √157
c ≈ 12.530 . . . . feet
The rope is about 12.5 feet long.
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Additional comment
The hypotenuse of a right triangle is longer than either leg, and is shorter than the sum of the two legs. That means ...
11 < c < 17
Only one answer choice fits.