Center – a point which is situated inside the circle and all the point which are on the circle are equally distance from the center.
Radius – it is defined as the distance which is measured form the center to any point on a circle. Or we can say it is the half of the Diameter.
Diameter – the distance this is inside the circle, and a Chord which passes through the center of a circle. Or it is twice the radius of a circle.
Circumference – the distance which is around or outside the circle is circumference of a circle. The meaning of word circumference is curved lines which reach around the circle.
If we have radius of a circle then the circumference of a circle using formula:
Circumference = 2⊼R,
‘R’ is the radius of the circle and the value of ‘⊼’ is 3.142.
Area – a circle has no area. Area means the surface which is enclosed by a circle.
Chord – a line in a circle which join two points.
Tangent – it is also a line which is passes through a circle and touching it one point only.
Secant – a line which intersect a circle in two half.
Now we see what is the general equation of a circle?
The general form of equation is:
x2 + y2 + Cx + Dy + E = 0.