A ladder 18 feet long is leaning against a wall that is perpendicular to level ground. The bottom of the ladder is 6 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 option.
A) 12.5 B) 15 C) 18 D) 19 E) 25
18^2-6^2=288   it means that the height is equal to 16.9.   since the top of the ladder slips down 4 feet, then the height of the wall =16.9-4= 
<gadget id="calculator">16.9-4</gadget>
<output>12.9</output>
12.9   the bottom=sqrt(18^2-12.9^2)=sqrt(324-166.41)=12.5   ans is 12.5
<result>A</result>
A ladder 18 feet long is leaning against a wall that is perpendicular to level ground. The bottom of the ladder is 6 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?