A herdman walks
10m due west and
then 10km due south
What is the displacement​

Answer is 14 Km (approx.)

Explanation:

Let the herdman's distance towards west be BC

Let the herdman's distance towards south be AC

So, we need to find length AB.

By Pythagoras Theorem,

(AB)² = (BC)² + (AC)²

= (10)² + (10)²

= 100 + 100

= 200

So, AB= √200 = 10√2 = 14 Km (approx.)

Hope it helps you

there is an explationation of this on a site called crash   course world history 1

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