## Question

### Solution

Correct option is

x2 + y2 = 2ax

Let the coordinates of A be (xy) and M be (α, β) (Fig.).

Since AM is parallel to OX,

α = x + a and β = y      ⇒     x = α – a and y = β

As A(xy) lies on the circle x2 + y2 = a2 we have    #### SIMILAR QUESTIONS

Q1

Three circles with radii 3 cm, 4 cm and 5 cm touch each other externally. If A is the point of intersection of tangents to these circles at their points of contact, then the distance of A from the points of contact is

Q2

A line meets the coordinate axes in A and B. A circle is circumscribed about the triangle OAB. If m and n are the distances of the tangent to the circle at the origin from the points A and B respectively, the diameter of the circle is

Q3

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Q4

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x2 + y2 – 4x + 2y + 4 = 0 orthogonally, is

Q5

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Q6

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Q7

If OA and OB are the tangents from the origin to the circle x2 + y2 + 2gx + 2fy + c = 0, and C is the centre of the circle, the area of the quadrilateral OACB is

Q8

The angle between a pair of tangents drawn from a point P to the circle x2 + y2 + 4x – 6y + 9 sin2α + 13 cos2α = 0 is 2α. The equation of the locus of the point P is

Q9

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Q10

If common chord of the circle C with centre at (2, 1) and radius r and the circle x2 + y2 – 2x – 6y + 6 = 0 is a diameter of the second circle, then the value of r is