Answers

2016-01-25T22:58:50+05:30
It would come as 14.6m becoz u are given that ht of building is 20m and angle of elevation is 45 so applying trignomatric ratio   tan45=1base comes to be 20m and than applying tan60=root3 to whole fig. we get the answer. 
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2016-01-25T23:06:10+05:30
Tan 45=20÷x
=1=20÷x
=x=20
tan 60=h+20÷x
=√3=h+20÷x
=√3×x=h+20
=√3×20=h+20
=by transposition
=h=20√3-20
=h=20(√3-1)
so the height of the tower is
h=20(√3-1)
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