Oswego City School District
Regents Exam Prep Center: Solving Quadratic Equations With Complex Roots
These examples use the quadratic formula to solve quadratic equations. Learn what to do when the solution includes a complex number. Use the practice page and teacher resource page to enhance the lesson.
University of St. Andrews (UK)
University of St. Andrews: Quadratic Equations History
This site from the University of St. Andrews provides an extensive history of quadratic, cubic, and quartic equations including various historical figures and their contributions to modern methods of solving quadratics.