Q9 of 35 Page 219

The shadow of a tower is 27 m, when the angle of elevation of the sun has measure 30. When the angle of elevation of the sun has measure 60, find the length of the shadow of the tower.

Let AB be the tower and CB its shadow when the angle of elevation of the sun is 30⁰.



∠ACB = 30⁰


∠B = 90⁰


CB = 27 m


DB is the shadow of the tower when the angle of elevation of the sun is 60⁰.


In ∆ACB,





In ∆ADB,





The length of the shadow of the tower is 9 m.


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