A 13-m-long ladder reaches a window of a building 12 m above the ground. Determine the distance of the foot of the ladder from the building.
Ladder AB = 13 m and distance from the window BC = 12 m.
AC is the distance of the ladder from the building.
From the figure, ΔABC is a right triangle.
In a right angled triangle
(Hypotenuse) 2 = (Base)2 + (Height)2
where hypotenuse is the longest side.
(AB)2 = (AC)2 + (BC)2
⇒132 = (AC) 2 + (12) 2
⇒ AC2 = 169- 144 = 25
⇒ AC = 5 m
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