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Question
Two vertical poles of different heights are standing 20m away from each other on the level ground. The angle of elevation of the top of the first pole from the foot of the second pole is 60° and angle of elevation of the top of the second pole from the foot of the first pole is 30°. Find the difference between the heights of two poles. (Take `sqrt(3)` = 1.73)
Solution
In ΔPQS, tan 60° = `y/20` ⇒ y = `20sqrt(3)` cm
In ΔRSQ, tan 30° = `x/20` ⇒ x = `20sqrt(3)` m
y – x = `20sqrt(3) - 20/sqrt(3) = 40/sqrt(3) = (40sqrt(3))/3` = 23.06 m
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