Application of Pythagorean Theorem. Solution: Let OA be the rope of the swing, CD be the ground plane, BC be the person who is 5 feet tall, AE be two steps, which is equivalent to the distance of 10 foot, there is a pedal at A, and EC is the distance from the pedal to 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.