Q. The angle between the tangents drawn at the points (5, 12) and $(12,\ - 5)$ to the circle $x^{2} + y^{2} = 169$ is
A) $45{^\circ}$
B) $60{^\circ}$
C) $30{^\circ}$
D) $90{^\circ}$
Explanation
(d)
Since, both the points lie on the circle. At (5, 12), equation of tangent is
$5x + 12y = 169$ …(i)
At $(12,\ - 5)$, equation of tangent is
$12x - 5y = 169$ …(ii)
It is clear that Eqs. (i) and (ii) are perpendicular to each other.
Hence, angle between them is $90{^\circ}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.