How to Subtract and Make Negative Numbers Using the TI-83 Plus

By Vanessa Molden

Updated September 28, 2017

The TI-83 Plus Graphing Calculator is an invaluable tool, but learning to use it properly can be a little slow-going at first. This article will explain the difference between subtracting numbers, and creating negative numbers with the TI-83 Plus.

How to Subtract and Make Negative Numbers Using the TI-83 Plus

Creating negative numbers: To create negative numbers, you will use the "negative" key (-) which is located below the "3" key. So, for instance, to type the number -9, you will first press the "-" key and then the "9" key.

Subtracting: The "negative" key is not used for subtracting. Instead, use the "subtraction" key. It is the third blue key up from the bottom on the right hand side of the calculator, just above the "addition" key (+). For instance, to type "9-5", you will first press the "9" key, then the blue "subtraction" key, and finally the "5" key.

Putting it together using parenthesis:

The left and right "parenthesis" keys are located above the "8" and "9" respectively. Parenthesis make it possible to actually use negative numbers in subtraction problems. For instance, you can subtract negative four from negative eight by typing (-8)-(-4). Press the left "(", then the "negative" key, then the "8", and close it with the right ")". Then use the blue "subtraction" key, followed by the left "(" key, the "negative" key, and the "4", and close the second set of parenthesis off with the right ")" key. If you hit the "enter" key", the solution should appear as "-4". Always be sure to close off sets of parenthesis, or else the calculator will display an error message.