A ladder 14 feet long is leaning against a wall that is perpendicular to level ground. The bottom of the ladder is 5 feet from the base of the wall. If the top of the ladder slips down 4 feet, how many feet will the bottom of the ladder slip?
Choose the correct choice from the following choices
A) 4	B) 5	C) 8	D) 10.72	E) 15

Rationale: "14 ^ 2 - 5 ^ 2 = 171 it means that the height is equal to 13.07 ~ = 13 . since the top of the ladder slips down 4 feet , then the height of the wall = 13 - 4 = 9 the bottom = sqrt ( 14 ^ 2 - 9 ^ 2 ) = sqrt ( 196 - 81 ) = 10.72 ans is d"
Answer: D