Quadratic graph lines are U- or Ո-shaped, which is called a parabola. A linear graph can be drawn using only three points. A quadratic graph is a curve, so more points are plotted to support accuracy.

As part of a series of electronic professional development experiences for educators, the NASA Explorer Schools project is hosting a 60-minute Web seminar on Sept. 27, 2011, at 8 p.m. EDT. Investigate ...