Texas Instruments TI-83 PLUS - Manual (Page 251)

TI-83 Plus Split Screen 248
Using Split Screen
Setting a Split-Screen Mode
To set a split-screen mode, press z , and then move the cursor to the
bottom line of the mode screen.
•
Select Horiz (horizontal) to display the graph screen and another
screen split horizontally.
•
Select G . T (graph-table) to display the graph screen and table screen
split vertically.
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The split screen is activated when you press any key that applies to
either half of the split screen.