Cambridge IGCSE Mathematics · Syllabus 0580 · Coordinate Geometry
Equations of Linear Graphs
What is Equations of Linear Graphs?
An algebraic relationship satisfied by the coordinates of every point on a straight line and by no other point. On the Core route two forms are needed: y = mx + c, which shows the gradient m and the y-intercept c directly, and x = k, which describes a vertical line and is the only straight line that cannot be written as y = mx + c. The Extended route adds other forms of the same line, in particular the integer form ax + by = c, and the point-gradient form y - y1 = m(x - x1) built from one known point and the gradient.
This definition is part of the Coordinate Geometry chapter in Cambridge IGCSE Mathematics.