question_answer

From a roof of a \[15\,\,m\] high house the angle of elevation of a point located \[15\,\,m\] distant to the base of the house is:

A) \[{{45}^{o}}\]                                    

B) \[{{30}^{o}}\]

C)  \[{{60}^{o}}\]                                   

D) \[{{90}^{o}}\]

Correct Answer: A

Solution :

Let the height of the roof be\[15\,\,m\]. In\[\Delta \,ABC\],                 \[\tan \theta =\frac{BC}{AB}\]                          \[=\frac{15}{15}=1\] \[\Rightarrow \]                     \[\theta ={{45}^{o}}\]