How to find max and min of a quadratic function


Explain why the graph of quadratic function could not contain both a minimum vertex and maximum vertex at the same time.
Your explanation should be 3-4 sentences and include at least 6 of the following words.
-U-shaped graph
-Y-value of the vertex
-X-value of the vertex
-quadratic function


A parabola, a graph of a quadratic function, cannot have a maximum vertex and a minimum vertex at the same time because of the shape of the graph.  A parabola is a u-shaped graph.  The vertex of the parabola is the point where the u changes direction; if it was increasing, it starts to decrease, and if it was decreasing, it starts to increase.  Since a parabola only changes direction once, there will either be a minimum or a maximum, not both.