The functions f(x) = –(x − 1)^2 + 5 and g(x) = (x + 2)^2 − 3 have been rewritten using the completing-the-square method. is the vertex for each function a minimum or a maximum? explain your reasoning for each function.

The vertex form of a quadratic function:
(h,k) - the coordinates of the vertex 

If a>0, then the parabola opens upwards, so the vertex is the minimum of the function.
If a<0, then the parabola opens downwards, so the vertex is the maximum of the function.

a=-1<0
the vertex is maximum

a=1>0
the vertex is minimum