At a point 15 m away from the base of a 15 m high house, the angle of elevation of the top is

• A

  $90^{\circ}$
• B

  $60^{\circ}$
• Correct answer
  C

  $45^{\circ}$
• D

  $30^{\circ}$

Solution

$\tan \theta=\frac{\mathrm{AB}}{\mathrm{AC}}=\frac{15}{15}=1$ $\Rightarrow \quad \tan \theta=\tan 45^{\circ}$ $\therefore \quad \theta=45^{\circ}$ $\therefore$ Angle of elevation $=45^{\circ}$.

Hence, the correct answer is option: 'C'.