# circle

## Family of Circles – Equations & Examples

Here you will learn equation of family of circles with examples. Let’ begin – Family of Circles (a)  The equation of the family of circles passing through the point of intersection of two circles $$S_1$$ = 0 & $$S_2$$ = 0 is : $$S_1$$ + K$$S_2$$ = 0      (K $$\ne$$ -1) (b)  The …

## Common Tangent to Two Circles – Direct and Transverse

Here you will learn common tangent to two circles i.e direct and transverse common tangents to two circles. Let’s begin – Common Tangent to Two Circles Let two circles having centers $$C_1$$ and $$C_2$$ and radii, $$r_1$$ and $$r_2$$ and $$C_1$$$$C_2$$ is the distance between their centres then : (a)  Both circles will touch : …

## Diameter Form of Circle – Equation and Examples

Diameter Form of Circle Equation The equation of the circle drawn on the straight line joining two points $$(x_1, y_1)$$ and $$(x_2, y_2)$$ is ($$x-x_1$$)($$x-x_2$$) + ($$y-y_1$$)($$y-y_2$$) = 0. This is known as diameter form of circle. where $$(x_1, y_1)$$ and $$(x_2, y_2)$$ are coordinates of two ends of diameter of circle. Note – If …

## Equation of Normal to a Circle with Examples

The normal at a point is the straight line which is perpendicular to the tangent to circle at the point of contact. Normal at a point of the circle passes through the center of circle. Here, you will learn how to find equation of normal to a circle with example. Equation of Normal to a …

## Equation of Tangent to a Circle – Condition of Tangency

When a straight line meet a circle on two coincident points then it is called the tangent to a circle. Here, you will learn condition of line to be a tangent  to a circle and equation of tangent to a circle with example. Condition of Tangency : The line L = 0 touches the circle …

## General Equation of the Circle – Formula and Examples

What is a Circle ? A circle is the locus of a point which moves in a plane in such way that its distance from a fixed point(in the same given plane) remains constant. The fixed point is called center of circle and the constant distance is called radius of the circle. The general equation …