Question

A straight line moves such that the algebraic sum of the perpendicular drawn to it from two fixed points is equal to $2k$, then the straight line always touches a fixed circle of radius

• A. $2k$
• B. $\frac{k}{2}$
• C. $k$
• D. none of these

Answer 1

The correct option is C $k$

Given that tha algehraic sum of the perpendicular drawn from to fixed points =2k

Such that 2 k=2 r

The perpendicular drawn to the center of the circle,such that they are equal to the radius of circle

$\Rightarrow$ 2k=2r

$\therefore k=r$

$\therefore$ Fixed radius of circle $=k$