Ellipses were introduced in three prior lessons:
In this current section, an ellipse is positioned with its center at the origin and foci on the $x$axis.If you're short on time, jump right to the summary of equations of ellipses.

they are the intersection points of the ellipse and the line through the foci. The major axis of the ellipse is the line segment that connects the vertices. Its length is the ellipse constant, $\,k\,$. An ellipse ‘shows’ its ellipse constant as the length of its major axis! The center of an ellipse is the midpoint of the major axis. You might roughly want to think of the major axis as giving the ‘length’ of the ellipse, and the minor axis (the segment from $\,I_3\,$ to $\,I_4\,$) as giving the ‘width’ of the ellipse. The major axis is always longer than the minor axis. 


At this point, we need additional notation and observations.




On this exercise, you will not key in your answer. However, you can check to see if your answer is correct. 
PROBLEM TYPES:
IN PROGRESS 