Khan Academy: Algebra: Foci of an Ellipse

The foci of an ellipse are explored in this video. First, foci are shown as the two points on the central axis such that the sum of the distance from a point on the ellipse and the foci points is the same as the distance from any point...

The foci of an ellipse are explored in this video. First, foci are shown as the two points on the central axis such that the sum of the distance from a point on the ellipse and the foci points is the same as the distance from any point...

A video lesson exploring the foci of an ellipse. The formula for finding the foci is derived algebraically and then applied to a specific ellipse equation. [13:49]

A video lesson exploring the foci of a hyperbola. The formula for finding the foci is derived algebraically and then applied to a specific hyperbola equation. Shows that the foci of a hyperbola relate closely to the foci of an ellipse....

This video demonstrates how to solve an equation that contains absolute values. It also shows how to check your answer. This video also appears in the strand Algebra: Absolute Value. [3:26]

A continuation of the Khan Academy video lesson series on identifying conic sections. This segment goes through examples that cover identifying and graphing both a circle and a parabola. [11:34]

A video lesson that goes through four example problems dealing with conic sections. Topics covered include: finding the vertex of a parabola from its equation; finding the asymptotes of a hyperbola and then sketching its graph;...

Video simplifying a rational algebraic expression with fractional exponents and a square root. [6:32]

A step-by-step instructional video on how to solve a ratio problem using algebra. [9:58]

Video simplifying an algebraic expression with negative exponents and then evaluating it when x equals 2. [2:19]