Following work of Heindl and of Powell and Sabin, each triangle of an arbitrary (regular) triangulation $\Delta$ of a polygonal region $\Omega$ in $\Bbb R^2$ is subdivided into twelve triangles, using ...

In this part you do not have to sketch the graph and you may even be given the sketch of the graph to start with. For a quadratic equation of the form \(y = k{(x - a)^2} + b\), the following diagram ...