On the Y= screen, I am having difficulty when I try to graph more than one function. When I highlight the = sign for the second function, the highlight turns off on the = sign for the first function. How do I fix this?

You must cast the functions in the so-called functional form y=ax+b. Isolate y for both functions, then open the Y= function editor and type in the second member (right member) of y=ax+b.
You can enter both functions and have them graphed on the same screen. In that case one will be on the Y1= line, the other on the second line.
Make sure that both = signs in the Y= editor are highlighted if you want both functions on the same graph.

Here it is.
When you enter a function you should press [ENTER] to validate. At the same time, the cursor moves to the next line. Verify that the = sign on the equation already entered is still highlighted.
If for some reason the = sign of an equation is no longer highlighted, use arrow keys to move cursor on the = sign and press [ENTER].

If only one = sign remains highlighted and all others are not, then in all probability the application Transfrm has been executed before and is still lingering in RAM. When in RAM, it takes over the graphing capabilities of the native OS. This prevents you from drawing more than one graph.You must unload it from memory.

1. Press the [APPS] key.
2. Scroll down to the line that shows Transfrm.
   
3. Highlight it and press [ENTER].
4. In following screen you are invited to Uninstall or continue.
5. Press the number to the left of Uninstall. Validate if need be.
6. Return to the Y= editor to type in functions to graph.

The fact that you are asking how to graph makes believe that you solved the problem about 'invalid dimension' . I am glad that worked for you.

This should help you setup your calculator to do graphing.

1. Prepare calculator for graphing Turn StatPlotsOff to avoid errors:

Press [2nd][STATPLOT][4:PlotsOff][ENTER].


2. Setup Graph type

• Press [MODE] key.
• In Mode set up screen, make set the angle unit (if you are drawing trigonometric functions)..
• Use the arrows to move cursor to 3rd line to highlight degree or radian and press [ENTER]. The important thing is that you be aware of the unit so that you do not get unexpected results.
  
• On same screen, verify that Func is highlighted. If you are drawing PARametric plots, POLar plots or SEQuence plots, you highlight the relevant item in the list
  
• If it is not, use arrow to highlight Func and press [ENTER] to validate.
• Do not worry if you do not have exactly the same screen as in the screen picture (We may have different OS Versions)
  

3. Entering the functions to draw (assuming you want to draw y= functions)

• Press [Y=] to enter function editor.
• Type in a function
  
• Press [ENTER] at the end of each function.
• Before pressing [GRAPH], make sure that all the = signs that define the functions to be graphed are highlighted white on black. If one is not highlighted, use arrow to move cursor on the sign and press [ENTER].
• In the screen capture 4 functions are slated to be drawn.
  

4. Selecting the Graph Style (You may ignore this now, because it is unimportant for just one graph)

• Select the graph style: The small piece of line to the left of a Y that defines a function is the style.
  
• Move cursor on it and press [ENTER] .
  
• Each [ENTER] (on same line) selects another style.
• On the next screen you have all the styles available on the calculator.
• Do not select the bubble on line 6: It is for animations. It will not leave a trace at the end of the plot.
  

5. Drawing the Graphs

• Press [GRAPH] to see the graphs.
• If one of them is missing, verify that its = is still highlighted, then use the [WINDOW] to set the Window dimensions,
• Here are the dimensions of the standard window
  

6. ZOOMING
You can also press [ZOOM] to adjust.



The selection 6:ZStandard sets the dimensions as on the screen Titled Window (above).

This should help you setup your calculator to do graphing.

1. Prepare calculator for graphing Turn StatPlotsOff to avoid errors:

Press [2nd][STATPLOT][4:PlotsOff][ENTER].


2. Setup Graph type

• Press [MODE] key.
• In Mode set up screen, make set the angle unit (if you are drawing trigonometric functions)..
• Use the arrows to move cursor to 3rd line to highlight degree or radian and press [ENTER]. The important thing is that you be aware of the unit so that you do not get unexpected results.
  
• On same screen, verify that Func is highlighted. If you are drawing PARametric plots, POLar plots or SEQuence plots, you highlight the relevant item in the list
  
• If it is not, use arrow to highlight Func and press [ENTER] to validate.
• Do not worry if you do not have exactly the same screen as in the screen picture (We may have different OS Versions)
  

3. Entering the functions to draw (assuming you want to draw y= functions)

• Press [Y=] to enter function editor.
• Type in a function
  
• Press [ENTER] at the end of each function.
• Before pressing [GRAPH], make sure that all the = signs that define the functions to be graphed are highlighted white on black. If one is not highlighted, use arrow to move cursor on the sign and press [ENTER].
• In the screen capture 4 functions are slated to be drawn.
  

4. Selecting the Graph Style (You may ignore this now, because it is unimportant for just one graph)

• Select the graph style: The small piece of line to the left of a Y that defines a function is the style.
  
• Move cursor on it and press [ENTER] .
  
• Each [ENTER] (on same line) selects another style.
• On the next screen you have all the styles available on the calculator.
• Do not select the bubble on line 6: It is for animations. It will not leave a trace at the end of the plot.
  

5. Drawing the Graphs

• Press [GRAPH] to see the graphs.
• If one of them is missing, verify that its = is still highlighted, then use the [WINDOW] to set the Window dimensions,
• Here are the dimensions of the standard window
  

6. ZOOMING
You can also press [ZOOM] to adjust.



The selection 6:ZStandard sets the dimensions as on the screen Titled Window (above).

This should help you setup your calculator to do graphing.

Prepare calculator to graph

Turn StatPlotsOff to avoid errors:
Press [2nd][STATPLOT][4:PlotsOff][ENTER].


Setup Graph type

• Press [MODE] key.
• In Mode set up screen, make set the angle unit (if you are drawing trigonometric functions)..
• Use the arrows to move cursor to 3rd line to highlight degree or radian and press [ENTER]. The important thing is that you be aware of the unit so that you do not get unexpected results.
  
• On same screen, verify that Func is highlighted. If you are drawing PARametric plots, POLar plots or SEQuence plots, you highlight the relevant item in the list
  
• If it is not, use arrow to highlight Func and press [ENTER] to validate.
• Do not worry if you do not have exactly the same screen as in the screen picture (We may have different OS Versions)
  

Entering the functions to draw (assuming you want to draw y= functions)

• Press [Y=] to enter function editor.
• Type in a function
  
• Press [ENTER] at the end of each function.
• Before pressing [GRAPH], make sure that all the = signs that define the functions to be graphed are highlighted white on black. If one is not highlighted, use arrow to move cursor on the sign and press [ENTER].
• In the screen capture 4 functions are slated to be drawn.
  

Selecting the Graph Style (You may ignore this now, because it is unimportant for just one graph)

• Select the graph style: The small piece of line to the left of a Y that defines a function is the style.
  
• Move cursor on it and press [ENTER] .
  
• Each [ENTER] (on same line) selects another style.
• On the next screen you have all the styles available on the calculator.
• Do not select the bubble on line 6: It is for animations. It will not leave a trace at the end of the plot.
  

Drawing the Graphs

• Press [GRAPH] to see the graphs.
• If one of them is missing, verify that its = is still highlighted, then use the [WINDOW] to set the Window dimensions,
• Here are the dimensions of the standard window
  

ZOOMING
You can also press [ZOOM] to adjust.



The selection 6:ZStandard sets the dimensions as on the screen Titled Window (above).

Read the first part of the answer to deactivate the statistical plots. No need to read the rest if you know how to do graphs.

Prepare calculator to graph

Turn StatPlotsOff to avoid errors:
Press [2nd][STATPLOT][4:PlotsOff][ENTER].


Setup Graph type

• Press [MODE] key.
• In Mode set up screen, make set the angle unit (if you are drawing trigonometric functions)..
• Use the arrows to move cursor to 3rd line to highlight degree or radian and press [ENTER]. The important thing is that you be aware of the unit so that you do not get unexpected results.
  
• On same screen, verify that Func is highlighted. If you are drawing PARametric plots, POLar plots or SEQuence plots, you highlight the relevant item in the list
  
• If it is not, use arrow to highlight Func and press [ENTER] to validate.
• Do not worry if you do not have exactly the same screen as in the screen picture (We may have different OS Versions)
  

Entering the functions to draw (assuming you want to draw y= functions)

• Press [Y=] to enter function editor.
• Type in a function
  
• Press [ENTER] at the end of each function.
• Before pressing [GRAPH], make sure that all the = signs that define the functions to be graphed are highlighted white on black. If one is not highlighted, use arrow to move cursor on the sign and press [ENTER].
• In the screen capture 4 functions are slated to be drawn.
  

Selecting the Graph Style (You may ignore this now, because it is unimportant for just one graph)

• Select the graph style: The small piece of line to the left of a Y that defines a function is the style.
  
• Move cursor on it and press [ENTER] .
  
• Each [ENTER] (on same line) selects another style.
• On the next screen you have all the styles available on the calculator.
• Do not select the bubble on line 6: It is for animations. It will not leave a trace at the end of the plot.
  

Drawing the Graphs

• Press [GRAPH] to see the graphs.
• If one of them is missing, verify that its = is still highlighted, then use the [WINDOW] to set the Window dimensions,
• Here are the dimensions of the standard window
  

ZOOMING
You can also press [ZOOM] to adjust.



The selection 6:ZStandard sets the dimensions as on the screen Titled Window (above).

This should help you setup your calculator to do graphing.

Prepare calculator to graph

Turn StatPlotsOff to avoid errors:
Press [2nd][STATPLOT][4:PlotsOff][ENTER].


Setup Graph type

• Press [MODE] key.
• In Mode set up screen, make set the angle unit (if you are drawing trigonometric functions)..
• Use the arrows to move cursor to 3rd line to highlight degree or radian and press [ENTER]. The important thing is that you be aware of the unit so that you do not get unexpected results.
  
• On same screen, verify that Func is highlighted. If you are drawing PARametric plots, POLar plots or SEQuence plots, you highlight the relevant item in the list
  
• If it is not, use arrow to highlight Func and press [ENTER] to validate.
• Do not worry if you do not have exactly the same screen as in the screen picture (We may have different OS Versions)
  

Entering the functions to draw (assuming you want to draw y= functions)

• Press [Y=] to enter function editor.
• Type in a function
  
• Press [ENTER] at the end of each function.
• Before pressing [GRAPH], make sure that all the = signs that define the functions to be graphed are highlighted white on black. If one is not highlighted, use arrow to move cursor on the sign and press [ENTER].
• In the screen capture 4 functions are slated to be drawn.
  

Selecting the Graph Style (You may ignore this now, because it is unimportant for just one graph)

• Select the graph style: The small piece of line to the left of a Y that defines a function is the style.
  
• Move cursor on it and press [ENTER] .
  
• Each [ENTER] (on same line) selects another style.
• On the next screen you have all the styles available on the calculator.
• Do not select the bubble on line 6: It is for animations. It will not leave a trace at the end of the plot.
  

Drawing the Graphs

• Press [GRAPH] to see the graphs.
• If one of them is missing, verify that its = is still highlighted, then use the [WINDOW] to set the Window dimensions,
• Here are the dimensions of the standard window
  

ZOOMING
You can also press [ZOOM] to adjust.



The selection 6:ZStandard sets the dimensions as on the screen Titled Window (above).

Prepare calculator to graph

Turn StatPlotsOff to avoid errors:
Press [2nd][STATPLOT][4:PlotsOff][ENTER].


Setup Graph type

• Press [MODE] key.
• In Mode set up screen, make sure that the angle unit is the degree.
• Use the arrows to move cursor to 3rd line to highlight {degree} and press [ENTER]
• On same screen, verify that Func is highlighted.
• If it is not, use arrow to highlight Func and press [ENTER] to validate.
• Do not worry if you do not have exactly the same screen as in the screen picture (We may have different OS Versions)
  

Entering the functions to draw.

• Press [Y=] to enter function editor.
• Type in a function
  
• Press [ENTER] at the end of each function.
• Before pressing [GRAPH], make sure that all the = signs that define the functions to be graphed are highlighted white on black. If one is not highlighted, use arrow to move cursor on the sign and press [ENTER].
• In the screen capture 4 functions are slated to be drawn.
  

Selecting the Graph Style (You may ignore this now, because it is unimportant for just one graph)

• Select the graph style: The small piece of line to the left of a Y that defines a function is the style.
  
• Move cursor on it and press [ENTER] .
  
• Each [ENTER] (on same line) selects another style.
• On the next screen you have all the styles available on the calculator.
• Do not select the bubble on line 6: It is for animations. It will not leave a trace at the end of the plot.
  

Drawing the Graphs

• Press [GRAPH] to see the graphs.
• If one of them is missing, verify that its = is still highlighted, then use the [WINDOW] to set the Window dimensions,
• Here are the dimensions of the standard window
  

ZOOMING
You can also press [ZOOM] to adjust.



The selection 6:ZStandard sets the dimensions as on the screen Titled Window (above).

In the window screen you can set Xmin=-180, Xmax=180, Xscl=10, Ymin= -0.6, Ymax= 1.5, Yscl=1. The minus here is the change sign (-) to the right of the [.] dot.

Prepare calculator to graph

Turn StatPlotsOff to avoid errors:
Press [2nd][STATPLOT][4:PlotsOff][ENTER].


Setup Graph type

• Press [MODE] key.
• In Mode set up screen, make set the angle unit (if you are drawing trigonometric functions)..
• Use the arrows to move cursor to 3rd line to highlight degree or radian and press [ENTER]. The important thing is that you be aware of the unit so that you do not get unexpected results.
  
• On same screen, verify that Func is highlighted. If you are drawing PARametric plots, POLar plots or SEQuence plots, you highlight the relevant item in the list
  
• If it is not, use arrow to highlight Func and press [ENTER] to validate.
• Do not worry if you do not have exactly the same screen as in the screen picture (We may have different OS Versions)
  

Entering the functions to draw (assuming you want to draw y= functions)

• Press [Y=] to enter function editor.
• Type in a function
  
• Press [ENTER] at the end of each function.
• Before pressing [GRAPH], make sure that all the = signs that define the functions to be graphed are highlighted white on black. If one is not highlighted, use arrow to move cursor on the sign and press [ENTER].
• In the screen capture 4 functions are slated to be drawn.
  

Selecting the Graph Style (You may ignore this now, because it is unimportant for just one graph)

• Select the graph style: The small piece of line to the left of a Y that defines a function is the style.
  
• Move cursor on it and press [ENTER] .
  
• Each [ENTER] (on same line) selects another style.
• On the next screen you have all the styles available on the calculator.
• Do not select the bubble on line 6: It is for animations. It will not leave a trace at the end of the plot.
  

Drawing the Graphs

• Press [GRAPH] to see the graphs.
• If one of them is missing, verify that its = is still highlighted, then use the [WINDOW] to set the Window dimensions,
• Here are the dimensions of the standard window
  

ZOOMING
You can also press [ZOOM] to adjust.



The selection 6:ZStandard sets the dimensions as on the screen Titled Window (above).

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.