From a point on the ground, the angles of elevation of the bottom and the top of a transmission tower fixed at the top of a 20 m high building are 45° and 60° respectively. Find the height of the tower
As per the question:
Let the height of building = p = 20 m
Therefore, total height of building and transmission tower = p’
The angle of elevation to the top of the building = 45° and that to the top of transmission tower = 60°
Height of transmission tower = ?
1st case:
2nd case: 
Now, the height of the tower can be calculated as:
p'- p = 20√3 - 20
= 20(√3 - 1)
= 20(1.732 - 1)
= 20 × 0.732
= 14.64 m
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