Revise how to recognise and determine the equation of a quadratic function from its graph. BBC Bitesize Scotland revision for SQA National 5 Maths.

If the graph of the quadratic function y = a x 2 + b x + c crosses the x-axis, the values of x at the crossing points are the roots or solutions of the equation a x 2 + b x + c = 0.

The top part of that image is the equation itself. The bottom part is a graph of the equation, which, as you can see, is exactly the same. To be fair, this equation cheats a little bit.