Q. The area (in square unit) of the circle which touches the lines $4x + 3y\text{=}15$ and $4x + 3y = 5$ is
A) $4\pi$
B) $3\pi$
C) $2\pi$
D) $\pi$
Explanation
(d)
Since, given lines are parallel.
$\therefore\ \ \ d = \frac{15 - 5}{\sqrt{4^{2} + 3^{2}}} = \frac{10}{5}$
$\Rightarrow \ d = 2 =$diameter of the circle
$\therefore$ Radius of circle$= 1$
$\therefore$ Area of circle$= \pi r^{2} = \pi$ sq unit
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.