Describe the graphs of r=2
`r^(2)=x^(2)+y^(2)`
`r=2`
Therefore `x^(2)+y^(2)=4` which is the equation of a circle whose center is at the origin and whose radius is 2

y=2x be a chord of the circle x^(2) +y^(2)=20x . Find the equation of a circle whose diameter is this chord.

x^(2)+y^(2)-6x+8y=56 What is the area of a circle whose equation is given above?

The equation of the circle whose center is (3,-2) and which touches the line 3x - 4y + 13 = 0 is

If the pole of a line w.r.t to the circle x^(2)+y^(2)=a^(2) lies on the circle x^(2)+y^(2)=a^(4) then find the equation of the circle touched by the line.

Find the equation of the system of circles co-axial with the circles x^(2)+y^(2)+4x+2y+1=0andx^(2)+y^(2)-2x+6y-6=0 Also, find the equation of that particular circle whose cneter lies on the radical axis.

x^2+y^2+4x-10y-20=0 The graph of the equation above is a circle with center (h, k) and radius r. Computer. r.(k-h) .

The equation of the circle with centre (3,2) and the power of (1,-2) w.r.t the circle x^(2)+y^(2)=1 , as radius is

Find the length of the chord x+ 2y = 5 of the circle whose equation is x^(2) + y^(2) = 9 . Determine also the equation of the circle described on the chord as diameter.

There are two perpendicular lines, one touches to the circle x^(2) + y^(2) = r_(1)^(2) and other touches to the circle x^(2) + y^(2) = r_(2)^(2) if the locus of the point of intersection of these tangents is x^(2) + y^(2) = 9 , then the value of r_(1)^(2) + r_(2)^(2) is.

Difference in the values of the radius of a circle whose center is at the origin and which touches the circle x^2+y^2-6x-8y+21=0 is_____________