A ladder 10 m long reaches a window 8 m above the ground. Find the distance of the foot of the ladder from the base of the wall.
Correct: A
Let the length of the ladder be the hypotenuse (c) of a right-angled triangle, c = 10 m.
Let the height of the window from the ground be one of the legs (a) of the triangle, a = 8 m.
Let the distance of the foot of the ladder from the base of the wall be the other leg (b).
Using the Pythagorean theorem: a² + b² = c².
8² + b² = 10²
64 + b² = 100
b² = 100 - 64
b² = 36
b = √36 = 6 m.
So, the distance of the foot of the ladder from the base of the wall is 6 m.