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Question
Two poles of height 9m and 14m stand on a plane ground. If the distance between their 12m, find the distance between their tops.
Solution
Let AB and CD be the two poles of height 14m and 9m respectively.
It is given that BD = 12m
∴ CE = 12m
Now,
AE = AB - BE
= 14m - 9m = 5m
Using Pythagoras theorem in ΔACE,
AC2 = AE2 + CE2
= (5m)2 + (12m)2
= 25m2 = 144m2
= 169m2
= 13m2
⇒ AC = 13m
Thus, the distance between the tops of the poles is 13m.
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