A man goes 80 m due east and then 150 m due north. How far is he from the starting point?
The starting point of the man is A and the last point is B so we need to find AB. 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
⇒ AB2 = (80) 2 + (150) 2 = 6400 + 22500 = 28900
⇒ AB = 170 m
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