Graphing Ellipses
Key Questions

The standard form of the ellipse is
#x^2/a^2+y^2/b^2=1# .The easiest way to graph it, is to make a rectangle, centered in the origin, having the horizontal sides with the lenght of
#2a# and the vertical sides with the lenght#2b# .The points
#(a,0),(0,b),(a,0),(0,b)# are the four vertices of the ellipse.It is sufficient now to join the four vertices.

It is a rather onerous process to do that. First, you'd need to convert the equation to
#y=# form, which means you'd get an ugly looking plus or minus square root function. Also, the processes involved in getting it to this form are very mistakeprone areas.However, there is an app in the TI84 called "Conics" (number 4 under apps) which does let you graph it very easily. Regrettably, this app doesn't have the graph features that the TI84 has (i.e. Table, Calc Zeroes, etc), and hence is pretty useless unless you want a general picture to see what it looks like. However, I found that this app can be very useful if you forget the formulae for any of your conics. Use it wisely ;)

It would be easiest to transform it first into standard form.