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Question
A person starts his trip from home. He moves 24 km in south direction and then starts moving towards east. He travels 7 km in that direction and finally reaches his destination. How far is the destination from his home?
Solution
Let A represent his home, AB represent the distance to the south, and BC represent the distance to the east.
Thus, distance between his destination and his home is AC.
According to the Pythagoras theorem,
AB2 + BC2 = AC2
Putting values for AB and BC in equation (i),
242 + 72 = AC2
576 + 49 = AC2
AC2 = 625
AC = `sqrt(625)` = 25
As a result, it is 25 kilometres between his home and his destination.
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