The diagram below shows the journey of the ship from the Base O to E, 6km in the North-East direction and then from E to N, 8km in the North direction. It is required to calculate the distance O to N. First extend NE backwards to the point E. Now consider the Rt Triangle OEB in which Angle EOB is 45 degrees.

On simplification this will be = √ ( 100+48√2)

= √(167.88)

= 12.96 km approx

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