Khan Academy
Khan Academy: Foci of an Ellipse From Equation
Given the equation of an ellipse, find its foci. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
CK-12 Foundation
Ck 12: Analysis: Equation of an Ellipse
[Free Registration/Login may be required to access all resource tools.] In this lesson students are provided with an introduction to conic sections and sketching ellipses. Students examine guided notes, review guided practice, watch...