Using the TI-83

Area

Press and select Conics.
We will select ELLIPSE for
this example.
The formulas for an ellipse
and the orientation of the graph
are shown.
Press ENTER, and you will be
able to insert values into
the formula.
After you have entered the
values, press GRAPH.
You can use the TRACE key,
but the CALC and TABLE
functions will not work.
This was graphed in
FUNCTION mode.
To graph in another mode,
select ELLIPSE as above, and
then press , and select
POL (polar) and MAN
(manual). Press ESC to return
to the ELLIPSE window.
Now we will graph an ellipse in polar
mode.
Scroll down to
Equation 4. (Use the down cursor.)
Press ENTER and enter the
parameters e=0.97 and
p=0.551
Press to display the
CONIC ZOOM menu.
Select 1:Zoom Conic
You can use TRACE on this as well.
Press to exit the graph screen.
Then press then [SOLVE].
This will find the center and foci.