A variable chord is drawn through the origin to the circle `x^2+y^2-2a x=0` . Find the locus of the center of the circle drawn on this chord as diameter.

How many chords can be drawn through 20 points on a circle ?

The equation of tangents drawn from the origin to the circle x^2+y^2-2rx-2hy+h^2=0

How many chords can be drawn through 21 points on a circle?

Let A B be chord of contact of the point (5,-5) w.r.t the circle x^2+y^2=5 . Then find the locus of the orthocentre of the triangle P A B , where P is any point moving on the circle.

A pair of tangents are drawn from the origin to the circle x^2+y^2+20(x+y)+20=0 . Then find its equations.

From the origin, chords are drawn to the circle (x-1)^2 + y^2 = 1 . The equation of the locus of the mid-points of these chords is circle with radius

Through a fixed point (h, k) secants are drawn to the circle x^2 +y^2 = r^2 . Then the locus of the mid-points of the secants by the circle is

Two variable chords A Ba n dB C of a circle x^2+y^2=r^2 are such that A B=B C=r . Find the locus of the point of intersection of tangents at Aa n dCdot

A pair of tangents are drawn from the origin to the circle x^2 + y^2 + 20x +20y + 20 = 0 , The equation of pair of tangent is