Hi this is Rob. I am going to show you how to graph a circle

on the TI 84 Plus CE Graphing Calculator. To graph a circle on the TI 84 Plus CE we

are going to use the Conics App that is built into the calculator. To open the Conics App, press the apps button

here. The Applications list opens up. Go down to number 4, Conics and press enter. The types of conics that you can graph with

the Conics App are circles, ellipses, hyperbolas and parabolas. Go down to number 1, Circle and press the

enter key. Now we see two standard equations for a circle. The first equation is referred to as the standard

form and is also referred to as the center-radius form. The second equation is known as the General

Form equation for a circle. The general form is basicly the first equation

multiplied out. In this video we will use the first equation

and we will graph the following circle: x minus 3 squared plus y plus 4 squared equals

25. On the calculator choose one and press enter. This screen appears. To graph the circle we will need to know H,

K, and R. The numbers below are from a previous circle equation that I was graphing. Using our equation, H equals 3, K equals a

negative 4 and R squared equals 25. Now let’s plug in these numbers into the

calculator. H equals 3. I already have a 3 there. Now use the down arrow key and go to K. And

enter a negative 4 for K. Remember to use this negative sign here and not the minus

sign. But Rob, why use a negative four, it looks

like a positive 4. Well, the equations is y minus a negative

4. And a negative times a negative is a positive. That is why in the equation it is y plus 4. Go down to R. Now R squared equals 25. Thus take the square root of both sides and

R equals a plus or minus 5. Enter a positive 5 for R. Now press this graph

button here to graph the circle. Unfortunately the numbers of the graph are

not labeled. But you can press this trace button here and

then use the right or left arrow buttons to trace around the circle. The calculator will display the coordinates

of the trace on the bottom of the screen. To escape out of the trace, press the clear

button here. Remember, the center of a circle is at H,

K. In this equation, the center of our circle

is at 3, negative 4. To escape out of this graph, press the clear

button here. It will bring you back to this screen and

you can graph your next circle. To escape out of this screen press this y

equals key here. It will bring you back to this screen. Ok that is it. That is how to graph a circle on the TI 84

Plus CE Graphing Calculator. If you like this video, please give it a thumbs

up and please subscribe to this channel.

thanks my dood

Thank you!!!

The conix app is not on either one of my 3 8I-84 Plus CE and silver editions. Where are you getting this from?

How would you then graph a parabola with the circle? To find the points of intersection.

I want to makes circles with out the comics helps. Just raw equation… the hard way. Please helo