and the 
to move the cursor to the equal sign of the function to be turned on/off.
Turning a function off will not display it when the calculator graphs or displays a table.
and the to move the cursor to the equal sign of the function to be turned on/off.
If the equal sign is not highlighted then that function is turned off.
If the equal sign is highlighted then that function is turned off.
In this screen Y1 is turned on and Y2 is turned off.
