Application of Pythagorean Theorem. Let's assume that OA is the rope of the swing, CD is the ground plane, BC is a person who is 5 feet tall, AE is two steps, which is equivalent to the distance of 10 feet, there is a pedal at A, and EC is the distance between the pedal and the ground, which is equal to one foot.

Let OA=x, that is, OB = OA = X, FA = BE = BC-EC = 5- 1 = 4 feet, BF=EA= 10 feet.

In Rt△OBF, according to Pythagorean theorem,

OB2=OF2+BF2, that is, x2=(x-4)2+ 102,

Solve this equation and get x= 14.5 (feet).

So the rope length of this swing is 14.5 feet.