The constant term in the equation (the + 1 or ‒ 2) shows the point where the graph crosses the y -axis. This is known as the y -intercept and is represented by the letter c in y = m x + c.

GCSE Eduqas Straight line graphs - Eduqas y = mx + c y = mx + c is an important real-life equation. The gradient, m, represents rate of change (eg, cost per concert ticket) and the y-intercept, c ...