All straight line graphs have an equation that can be written in the form 𝑦 equals 𝑚𝑥 add 𝑐, where 𝑚, the coefficient of the 𝑥 term, is the gradient or slope of the line. The constant, 𝑐, is ...

Below is the graph of a quadratic function, showing where the function is increasing and decreasing. If we draw in the tangents to the curve, you will notice that if the gradient of the tangent is ...