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Question 12 Two poles of heights 6 m and 11 m stand on a plane ground. If the distance between the feet of the poles is 12 m, find the distance between their tops.
Solution:

Given, Two poles of heights 6 m and 11 m stand on a plane ground.

And distance between the feet of the poles is 12 m.

Let AB and CD be the poles of height 6m and 11m.

Therefore, CP = 11 – 6 = 5m

From the figure, it can be observed that AP = 12m

By Pythagoras theorem for ΔAPC, we get,

$AP^2 = PC^2 + AC^2$

$(12m)^2 + (5m)^2 = (AC)^2$

$AC^2 = (144+25) m^2 = 169 m^2$

AC = 13m

Therefore, the distance between their tops is 13 m.

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