Interaction between Circle and a Line

IMPORTANT

Interaction between Circle and a Line: Overview

This topic covers concepts such as Interaction between Line and a Circle, Position of a line with respect to a circle, Condition For Tangency to a Circle, Image of a Circle in a Line Mirror, Chord of a Circle, Length of the Chord of a Circle, etc.

Important Questions on Interaction between Circle and a Line

HARD
IMPORTANT

Find the point on the straight line, y = 2x + 11 which is nearest to the circle,  1 6 x 2 + y 2 + 3 2 x - 8 y - 5 0 = 0

HARD
IMPORTANT

One of the diameters of the circle circumscribing the rectangle ABCD is 4y=x+7. If A and B are the points - 3,4 and 5, 4, respectively, then the area of the rectangle is 

HARD
IMPORTANT

All the chords of the curve   3 x 2 y 2 2x+4y=0,  which subtend a right angle at the origin, pass through a fixed point. Find the coordinates of the point.

EASY
IMPORTANT

The points of intersection of the line   4x3y10=0 and the circle  x2+y22x+4y20=0 are:

MEDIUM
IMPORTANT

Let O be the center of the circle x2+y2=r2, where r>52. Suppose PQ is a chord of this circle and the equation of the line passing through P and Q is  2x+4y=5. If the center of the circumcircle of the triangle OPQ lies on the line x+2y=4, then the value of r is ______

MEDIUM
IMPORTANT

Equation of the circle, which is the mirror image of the circle x2+y2-2x=0 with respect to the line x+y=2, is

MEDIUM
IMPORTANT

If one of the diameters of the circle x2+y2-2x-6y+6=0 is a chord to the circle with centre 2, 1, then the radius of the circle is

MEDIUM
IMPORTANT

The circle x2+y2-3x-4y+2=0 cuts x-axis at

MEDIUM
IMPORTANT

The locus of centre of a circle which passes through the origin and cuts off a length of 4 unit from the line x=3 is

HARD
IMPORTANT

Radius of circle in which a chord length 2 makes an angle π2 at the centre, is

MEDIUM
IMPORTANT

If a circle of centre α2,0 and radius R touches by the line y=x and cuts off a chord of length 2 units along the line 3y-x=0. Then the value of 2α2R2 is equal to

MEDIUM
IMPORTANT

Let A, B, C be three points on a circle of radius 1 such that ACB=π4. Then the length of the side AB is

MEDIUM
IMPORTANT

Find the sum of square of the length of the chords intercepted by the line x+y=n; nN on the circle x2+y2=4.

HARD
IMPORTANT

Find the length of the chord intercepted by the circle x2+y2-x+3y-22=0 on the line y=x-3.

HARD
IMPORTANT

Set of values of m for which two points P and Q lie on the line y=mx+8 so that APB=AQB=π2 where A(-4,0),B(4,0) is -

HARD
IMPORTANT

If two distinct chords drawn from the point 22sinθ,12 to the circle x2+y2=22sinθx+12y, (θ is a parameter) are bisected by x -axis, then the exhaustive set in which θ lies is

HARD
IMPORTANT

Three parallel chords of a circle have lengths 2, 3, 4 and subtend angles α, β, α+β at the centre respectively (given α+β<π), then cosα is equal to

HARD
IMPORTANT

Let C1 and C2 are two circles x2+y2+10x-24y-87=0 and x2+y2-10x-24y+153=0 respectively. Let m be the smallest positive value of a for which the line y=ax contains the centre of a circle that is internally tangent to C1 and externally tangent to C2, then the value of m is (where [·] denotes greatest integer function)

HARD
IMPORTANT

If points (0, 0), (λ, 0),(0, λ) and μ-1, μ+3 are always concyclic μR (where λR and λ0, then minimum value of λ is

HARD
IMPORTANT

If the variable line 3x-4y+k=0 lies between the circles x2+y2-2x-2y+1=0 and x2+y2-16x-2y+61=0 without intersecting or touching either circle, then range of k is a,b where a, bI. Then the value of b-a, is