### Home > CCA > Chapter 9 > Lesson 9.1.2 > Problem 9-21

9-21.

For each quadratic function below, use the idea of completing the square to write it in graphing form. Then state the vertex of each parabola. Homework Help ✎

*f*(*x*) =*x*^{2}+ 4*x*+ 5*f*(*x*)*x*^{2}− 6*x*In both graphs, does the vertex represent the maximum or minimum value of the parabola?

Draw tiles to help you make the expression into a square.

Put it into graphing form and from there figure out the vertex.

*f*(*x*) = (*x* + 2)^{2} + 1,

vertex: (−2, 1)

See part (a).

Is the vertex the highest (maximum) or lowest (minimum) point on the graph?