Computing the axis of symmetry before constructing a table to graph a quadratic equation.

1. The x-coordinate of the vertex is given by x = -b/2a.
2. Now we are ready to construct a table of values.

3. Computing the corresponding values for the y-coordinates.
4. Graphing the parabola.
5. Since a is positive the parabola has a minimum, i.e. It opens upwards.

6. In this case the roots are imaginary, since square roots of negatives give imaginary or complex results. Only points in the x-axis, give real roots.