When graphing the function (x+6)/(x-7) I'm getting a vertical line showing up on the graph connecting the two curves that shouldn't be there. do I have something turned on that shouldn't be?

At first, in menu choose settings and set on Graphing Angle option to Radian. Then graph function. See captured image

I have drawn the curve for your function. On my TI84Plus with OS version 2.53MP the spurious asymptotes do not show, while on a TI83PLUS OS 1.12 they do if the graph is drawn as connected lines. It might be a bug that was corrected in newer OS (for TI84PLUS)



The graph from a TI83PLUS (the last one above) shows asymptotes when drawn connected, but no asymptotes appear if graph is drawn dotted.
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There is no vertical (or otherwise) asymptote feature on a TI84PLUS. It seems to you that the calculator is drawing the asymptote. However when you plot a CONNECTED Graph a line is drawn from one point to the next: The last point on one side of the asymptote is thus connected to the first point on the other side, effectively mimicking the drawing of the asymptote.
To get rid of this spurious effect, draw dotted graphs, but you will see fewer points, because the points are drawn at constant intervals in X. This is set by the Xres variable, in the Window configuration screen.

Here is a function that will "show" you a vertical asymptote on the TI84PLus, when graph is drawn connected, but on a calculator with a higher resolution, you see none. A calculator cannot handle infinity. You can with the help of your mind's sight, so to speak, see the asymptote on the graph.

Ok, try these two things and you should be just fine.
1.) Check your range for your graph. It is possible that the range you are using isnt large enough to show the curve. Also try using Z-fit vs Z-st. These are options that your calculator will give you once the equation is graphed.
2.) Place a parenthesis around the 2x, make sure that you and the calculator are both using the same order of operations. This move mill ensure that the calculator will multiply the variable, x, by two and then do the exponential.
This should do it!
Happy Graphing!

I believe I already showed you with a profusion of details how to graph functions on the calculator. It would very kind of you to refer to the post that answered your question, so as not to make us answer it all over again. Much appreciated.

Read the following to use the intersection function.

1. You draw two or more graphs.
2. After the graphs are displayed, press [2nd][TRACE] to access the (CALC)ulate menu.
   
3. Select [5:Interesct]
4. You will be prompted for a first curve: the equation of the curve will be displayed at the top left corner of the screen. If it is one the intersecting curves, press [ENTER]
5. You will be prompted for the second curve. (You can move from one curve to another by pressing the UpArrow or DownArrow).
6. After two curves are selected, you will be prompted for a guess for the X-value of an intersection point: you can use the keypad to enter a guess or use the left or right arrow to move the cursor towards a point of your choosing (if there are more than one point).
7. After a short while the calculator gives you a solution.
8. If it fails, you must make a better guess.
   

Here are some screen captures

Here is the link to the manual.
Here is a short tutorial to get you started.
First thing to do before any new type of graphing problem
1. Turn StatPlots OFF : press [2nd][STATPLOT][4:PlotsOff] [ENTER]

Second thing: Clear the statistical lists
2. Press [2nd][0][PGRM] DownArrow to point to ClrAllLists.
3.Press [ENTER][ENTER]

Third thing : Configure the graph type to be FUNCTION graph
4. Press [MODE]. If FUNC (on fourth line) is highlighted. Press [Y=] and start entering the functions.
5. If FUNC is not highlighted, use Down arrow till 4th line, highlight FUNC and press [ENTER]. Press Press [Y=] and start entering the functions.

Fourth thing: Enter function and select them for graphing
1. As you start entering the function Y1=, notice that the = sign becomes highlighted. Press [ENTER] when Y1 is typed in. Make sure the = sign for Y1 remains highlighted as cursor moves to Y2=.
2. Keep entering the functions and verifying that their = signs remain highlighted as cursor moves to another equation.
3. When finished press [ENTER]
4. Look at the graph style for each function: it is a bit of line to the left of each Y. Here is a picture of all the 7 styles.



To set a graph style, highlight the style to the left of the Y, and press [ENTER]. Each time you press [ENTER] you see a new style, in the order shown on picture.
Avoid the style of Y6, it is bubble, and as such will burst and disappear once graph is finished. Avoid also the triangular ones (for Y3 and Y4) they will shade areas of the graph, and may hide other functions.

Fifth thing: Graph Functions.
1. You can press [GRAPH] to see your graphs.
2. If one curve is missing (and you have not set its style to be rhe bubble), it may be due to the Window dimensions.

Sixth Thing: Set Window dimensions and Zoom.
1. Press [ZOOM][6:ZStandard] to use standard window dimensions.
2. If curve still missing, Press [ZOOM][3:Zoom Out] to zoom out so that you may be able to see a bigger range for the functions.
3. If necessary press [WINDOW] and set the Xmin, Xmax, Ymin,Ymax to values of your own.



Dimensions must obey the conditions: Xmin < Xmax, and Ymin < Ymax.

Hello,

First thing to do before any new type of problem
1. Turn StatPlots OFF : press [2nd][STATPLOT][4:PlotsOff] [ENTER]

Second thing: Clear the statistical lists
2. Press [2nd][0][PGRM] DownArrow to point to ClrAllLists.
3.Press [ENTER][ENTER]

Third thing : Configure the graph type to be FUNCTION graph
4. Press [MODE]. If FUNC (on fourth line) is highlighted. Press [Y=] and start entering the functions.
5. If FUNC is not highlighted, use Down arrow till 4th line, highlight FUNC and press [ENTER]. Press Press [Y=] and start entering the functions.

Fourth thing: Enter function and select them for graphing
1. As you start entering the function Y1=, notice that the = sign becomes highlighted. Press [ENTER] when Y1 is typed in. Make sure the = sign for Y1 remains highlighted as cursor moves to Y2=.
2. Keep entering the functions and verifying that their = signs remain highlighted as cursor moves to another equation.
3. When finished press [ENTER]
4. Look at the graph style for each function: it is a bit of line to the left of each Y. Here is a picture of all the 7 styles.



To set a graph style, highlight the style to the left of the Y, and press [ENTER]. Each time you press [ENTER] you see a new style, in the order shown on picture.
Avoid the style of Y6, it is bubble, and as such will burst and disappear once graph is finished. Avoid also the triangular ones (for Y3 and Y4) they will shade areas of the graph, and may hide other functions.

Fifth thing: Graph Functions.
1. You can press [GRAPH] to see your graphs.
2. If one curve is missing (and you have not set its style to be rhe bubble), it may be due to the Window dimensions.

Sixth Thing: Set Window dimensions and Zoom.
1. Press [ZOOM][6:ZStandard] to use standard window dimensions.
2. If curve still missing, Press [ZOOM][3:Zoom Out] to zoom out so that you may be able to see a bigger range for the functions.
3. If necessary press [WINDOW] and set the Xmin, Xmax, Ymin,Ymax to values of your own.



Dimensions must obey the conditions: Xmin < Xmax, and Ymin < Ymax.

Hope that helps.

Hello,
You bet I do, provided
1. there are no hardware problems I am not aware of;
2. that you are willing to follow my instructions.

First thing to do before any new type of problem
1. Turn StatPlots OFF : press [2nd][STATPLOT][4:PlotsOff] [ENTER]

Second thing: Clear the statistical lists
2. Press [2nd][0][PGRM] DownArrow to point to ClrAllLists.
3.Press [ENTER][ENTER]

Third thing : Configure the graph type to be FUNCTION graph
4. Press [MODE]. If FUNC (on fourth line) is highlighted. Press [Y=] and start entering the functions.
5. If FUNC is not highlighted, use Down arrow till 4th line, highlight FUNC and press [ENTER]. Press Press [Y=] and start entering the functions.

Fourth thing: Enter function and select them for graphing
1. As you start entering the function Y1=, notice that the = sign becomes highlighted. Press [ENTER] when Y1 is typed in. Make sure the = sign for Y1 remains highlighted as cursor moves to Y2=.
2. Keep entering the functions and verifying that their = signs remain highlighted as cursor moves to another equation.
3. When finished press [ENTER]
4. Look at the graph style for each function: it is a bit of line to the left of each Y. Here is a picture of all the 7 styles.



To set a graph style, highlight the style to the left of the Y, and press [ENTER]. Each time you press [ENTER] you see a new style, in the order shown on picture.
Avoid the style of Y6, it is bubble, and as such will burst and disappear once graph is finished. Avoid also the triangular ones (for Y3 and Y4) they will shade areas of the graph, and may hide other functions.

Fifth thing: Graph Functions.
1. You can press [GRAPH] to see your graphs.
2. If one curve is missing (and you have not set its style to be rhe bubble), it may be due to the Window dimensions.

Sixth Thing: Set Window dimensions and Zoom.
1. Press [ZOOM][6:ZStandard] to use standard window dimensions.
2. If curve still missing, Press [ZOOM][3:Zoom Out] to zoom out so that you may be able to see a bigger range for the functions.
3. If necessary press [WINDOW] and set the Xmin, Xmax, Ymin,Ymax to values of your own.



Dimensions must obey the conditions: Xmin < Xmax, and Ymin < Ymax.

Hope that helps.



5

Hello,
I have answered this question multiple times. I have no idea why you calculator refuses to allow you to choose more graph styles. Maybe you should reset it by clearing the RAM.
Concerning the connected asymptotes.
In truth your function has one aymptote namely the straight line x=2 but your graph has two asymptotic branches, one tends towards -infinity, the other toward + infinity. That they seem connected is an illusion due to the finite resolution of the screen. This is made worse if you select a connected graph instead of a dotted one. I am enclosing a screen capture of the graph for the same function, drawn on a calculator with better resolution.



This clarification being given, it remains that you still have a problem since you cannot choose other styles. Do try to reset the RAM, and choose dotted graphs. If that does not work, maybe you should update the OS or reinstall it from education.ti.com.
I hope it solves your problem. If it does not, do not blame me, and remember that I tried my best.

Hello,
Use the [Y=] entry screen to enter the functions you want to graph. Make sure that the = sign after Y1, Y2 etc. is highlighted (black). If the = sign is not highlighted the corresponding function will not be drawn. You can can up to 10 functions, but what is the point of drawing so many if they overlap?
Anyway, to change the graph style of the curve for a particular function, use arrows to move to the line, then use left arrow to the bit of line that appears to the left of the Y. Highlight the segment an press ENTER. Each time you press ENTER the style changes to another one. Beware of the unconnected bubble style. During the drawing it will show the position of the point being drawn, but at the end, the whole curve, so to speak, evaporates.
As to simultaneous graphs, if it is important to you to have the graphs drawn for all the curves at the same time, you can enforce that by pressing [MODE], and using down arrow to reach the 6th line Sequential Simul. Use the right arrow to highlight Simul and press ENTER.
Whether drawn sequentially or simultaneously, all graphs will be displayed, except for the ones with the unconnected bubble as style.

Hope it helps.