SOLUTION: Find the quadratic function that has a vertex at (-1,3) and whose graph passes through the point (2,1).

All quadratic functions are in the form



or for convenience, let's write  for 



where the vertex is (,).

So since the vertex is (,), we plug those in







Now all we need is 

So we substitute (,) = (,).








So



becomes



or



in functional notation.

To draw the graph, plot the given vertex and the given
point, and find some more points, say: 

(-7,-5), (-4,1), (5,-5)



Now draw in the graph of the function:

 
Edwin