The set of all lines in the same plane that pass through a given point called the **centre of the pencil**.

### Examples

- Pencil of lines with its centre at the point with coordinates (3, 2) :

- In a Cartesian plane, a pencil of lines passing through a point with coordinates (
*p*,*q*) is a family defined by the equation \(y\space =\space \dfrac{q−b}{p}x + b\), where*b*is the*y*-intercept of each line in the pencil of lines.