An equation of the form \(y = mx + c\) where \(m\) and \(c\) are numbers, gives a straight line when values of \(x\) and corresponding values of \(y\) are plotted on a grid. A straight line is a ...

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 ...