<p>Can somebody explain how to do this with my TI-83+?</p>
<p>I already have some experience with programs. I created several basic trig programs.</p>
<p>The program I want to make would take an expression and plug it into "y=" so I can graph it.</p>
<p>For example</p>
<p>Prompt A
Prompt B
Prompt C
Store "Ax^2+BX+C" in "Y1" </p>
<p>Obviously I won't use this program for quadratic equations. This is just an example. I am trying to create a program to graph conics.</p>
<p>Hey, I figured out how to do this.</p>
<p><a href="http://www.arasian.com/vortex/83pbas/32.htm%5B/url%5D">http://www.arasian.com/vortex/83pbas/32.htm</a></p>
<p>Basically, you have to use string variables. Don't forget to use the quotes!!</p>
<p>This is how to create a program to graph an ellipse of form: (x-h)^2/a^2 + (y-k)^2/b^2=1</p>
<p>Prompt A
Prompt B
Prompt H
Prompt K
"K+sqrt(-(B^2/A^2)((X-H)^2-A^2))" <strong><em>HIT THE STORE KEY, VARS, STRING,Str1</em></strong>
"K-sqrt(-(B^2/A^2)((X-H)^2-A^2))" <strong><em>HIT THE STORE KEY, VARS, STRING,Str2</em></strong>
<strong><em>Hit 2nd, Hit 0, Find and hit enter on String->Equ</em></strong><em>Str1,Y3)
*</em><strong>Hit 2nd, Hit 0, Find and hit enter on String->Equ</strong>*Str2,Y4)</p>
<p>That's the program.</p>
<p>Now run it and enter the variables. Then hit graph. Get rid of the negative sign right after the sqrt but before the B^2 to make this a hyperbola function.</p>
<p>Here is the concise program for those of you who are master programmers.</p>
<p>Prompt A
Prompt B
Prompt H
Prompt K
"K+sqrt(-(B^2/A^2)((X-H)^2-A^2))"->Str1
"K-sqrt(-(B^2/A^2)((X-H)^2-A^2))"->Str2
String->Equ(Str1,Y3)
String->Equ(Str2,Y4)</p>