A ladder of length 41 m rests against a wall. If it reaches a height of 40 m from the ground, then the distance of the foot of the ladder from the wall is
9
Let the distance of the foot of the ladder from the wall = x
Using Pythagoras Theorem we have,
x2+402=412
x2=412−402
x2=1681−1600
x2=81
x=9 m