TI-84 Calculator Button Functions Explained

The TI-84 calculator has many buttons for arithmetic, graphing, statistics, algebra, matrices, fractions, and scientific calculations. Each button can perform more than one function. The primary function is printed directly on the button, while secondary functions usually appear above the button in a different color. The 2nd button activates these secondary functions.

The exact layout can vary slightly between the TI-84 Plus and TI-84 Plus CE. However, the main button functions are very similar. This guide explains the most commonly used TI-84 buttons and shows how to use them step by step.

1. ON Button

The ON button turns the calculator on.

How to use it

1. Press ON.
2. Wait for the home screen to appear.
3. Enter your calculation or select a calculator function.

The ON button can also be used with 2nd to turn the calculator off.

To turn off the calculator

1. Press 2nd.
2. Press ON.
3. The calculator turns off.

The calculator can also turn itself off after a period of inactivity to save battery power.

2. 2nd Button

The 2nd button activates the secondary function printed above another button.

For example, the square function is normally accessed with the x² button. The inverse square function, √, is usually the secondary function.

How to use a secondary function

1. Press 2nd.
2. Press the button containing the required secondary function.
3. The calculator performs the selected function.

For example, to calculate the square root of 25:

1. Press 2nd.
2. Press x².
3. Enter 25.
4. Press ENTER.

The display should show 5.

The 2nd button is one of the most important buttons because many advanced calculator functions are assigned to secondary keys.

3. ALPHA Button

The ALPHA button allows you to enter letters and other character functions printed above calculator buttons.

TI-84 calculators use letters for variables, lists, matrices, programs, and other functions.

How to enter a letter

1. Press ALPHA.
2. Press the button containing the desired letter.
3. The letter appears on the screen.

For example, to enter the variable X:

1. Press ALPHA.
2. Press the button labeled X.

Some models also support an ALPHA LOCK function for entering multiple letters.

4. Arrow Buttons

The four arrow buttons control the calculator cursor and allow you to move through menus and previous calculations.

The buttons are:

• Up arrow
• Down arrow
• Left arrow
• Right arrow

Common uses

You can use the arrow buttons to:

1. Move the cursor through an expression.
2. Select menu options.
3. Scroll through previous calculations.
4. Move around graph screens.
5. Edit equations.
6. Select items from lists.

Editing a calculation

If you enter an expression incorrectly:

1. Press the left or right arrow.
2. Move the cursor to the incorrect part.
3. Delete or replace the value.
4. Press ENTER to calculate the corrected expression.

The up arrow can also recall previous expressions from the home screen.

5. ENTER Button

The ENTER button tells the calculator to process an expression, confirm a selection, or execute a command.

Example

To calculate 15 × 4:

1. Enter 15.
2. Press ×.
3. Enter 4.
4. Press ENTER.

The result is 60.

The ENTER button is also used when selecting menu options and entering equations in many calculator applications.

6. Number Buttons

The number buttons from 0 through 9 are used to enter numerical values.

You can combine these buttons with mathematical operators and functions.

Example

To calculate 125 + 275:

1. Press 1, 2, 5.
2. Press +.
3. Press 2, 7, 5.
4. Press ENTER.

The answer is 400.

7. Decimal Point Button

The decimal point button enters decimal numbers.

Example

To calculate 3.5 × 2:

1. Enter 3.
2. Press the decimal point.
3. Enter 5.
4. Press ×.
5. Enter 2.
6. Press ENTER.

The answer is 7.

8. Mathematical Operation Buttons

The primary arithmetic buttons are:

• + for addition
• − for subtraction
• × for multiplication
• ÷ for division

Example

To calculate:

25 + 10 × 3

Enter:

1. 25
2. +
3. 10
4. ×
5. 3
6. ENTER

The TI-84 follows mathematical order of operations.

Use parentheses when you need to control the order of a calculation.

9. Negative Sign Button

The negative sign is used to enter negative numbers.

For example, to calculate:

−8 + 3

Press:

1. (-)
2. 8
3. +
4. 3
5. ENTER

The answer is −5.

Do not confuse the negative sign with the subtraction button. The TI-84 uses a separate (-) key for entering negative values.

10. Parentheses Buttons

Parentheses control the order in which calculations are performed.

Example

To calculate:

(10 + 5) × 3

Press:

1. (
2. 10
3. +
4. 5
5. )
6. ×
7. 3
8. ENTER

The answer is 45.

Parentheses are particularly useful when entering algebraic expressions, fractions, trigonometric calculations, and statistical formulas.

11. x² Button

The x² button squares a number.

Example

To calculate 12²:

1. Enter 12.
2. Press x².
3. Press ENTER.

The answer is 144.

The same button can provide the square root function through its secondary function.

12. Square Root Button

The square root function is accessed using the secondary function associated with the square button.

Example

To calculate √81:

1. Press 2nd.
2. Press x².
3. Enter 81.
4. Press ENTER.

The result is 9.

13. x⁻¹ Button

The x⁻¹ button calculates the reciprocal of a number.

The reciprocal of a number is:

1 ÷ x

Example

To calculate the reciprocal of 5:

1. Enter 5.
2. Press x⁻¹.
3. Press ENTER.

The answer is 0.2.

This function is useful in algebra, scientific calculations, and statistics.

14. Exponent Button

The caret or power button is used to raise one number to another power.

Example

To calculate 2⁵:

1. Enter 2.
2. Press ^.
3. Enter 5.
4. Press ENTER.

The result is 32.

You can also use this function for scientific notation and algebraic calculations.

15. LOG Button

The LOG button calculates the common logarithm, which has a base of 10.

Example

To calculate log(100):

1. Press LOG.
2. Enter 100.
3. Press ENTER.

The answer is 2.

The secondary function can provide the inverse logarithm function.

16. LN Button

The LN button calculates the natural logarithm.

Natural logarithms use the mathematical constant e as the base.

Example

To calculate ln(10):

1. Press LN.
2. Enter 10.
3. Press ENTER.

The calculator displays the natural logarithm of 10.

The secondary function provides the inverse natural logarithm function.

17. SIN, COS, and TAN Buttons

The TI-84 includes three primary trigonometric buttons:

• SIN for sine
• COS for cosine
• TAN for tangent

These functions can be used for angles in degrees or radians.

Example: sine of 30 degrees

First check the angle mode.

1. Press MODE.
2. Select Degree.
3. Press ENTER if required.
4. Press SIN.
5. Enter 30.
6. Press ENTER.

The answer should be 0.5.

Changing to radians

1. Press MODE.
2. Move to the angle settings.
3. Select Radian.
4. Press ENTER.

The calculator will then interpret trigonometric angles as radians.

18. MODE Button

The MODE button controls important calculator settings.

The MODE menu can control settings such as:

• Degree or radian angle mode
• Normal or scientific notation
• Float or fixed decimal display
• Function, parametric, polar, or sequence graphing modes
• Other calculation settings

How to change the angle mode

1. Press MODE.
2. Move the cursor to Degree.
3. Press ENTER.
4. Press 2nd.
5. Press MODE to return to the home screen.

Always check the angle mode before performing trigonometric calculations.

19. CLEAR Button

The CLEAR button removes information from the current screen or cancels certain selections.

On the home screen

Pressing CLEAR generally clears the current entry line.

To clear the entire calculator screen

1. Press CLEAR.
2. The current input is removed.

Do not confuse clearing the screen with resetting the calculator. Clearing an entry does not normally delete stored variables, programs, or other calculator data.

20. DEL Button

The DEL button deletes the character immediately before or at the cursor position, depending on the current screen.

How to delete part of an expression

1. Enter an expression.
2. Use the left or right arrow to move the cursor.
3. Place the cursor next to the unwanted character.
4. Press DEL.

This is useful when correcting equations without retyping the entire expression.

21. STAT Button

The STAT button opens the calculator's statistics functions.

You can use the STAT menu for:

• One-variable statistics
• Linear regression
• Quadratic regression
• Exponential regression
• Lists
• Statistical calculations

Example: entering a data list

1. Press STAT.
2. Select 1:Edit.
3. Enter data into L1.
4. Press ENTER after entering each value.
5. Use the arrow buttons to move through the list.

You can then use statistical calculations from the STAT menu.

22. MATH Button

The MATH button opens additional mathematical functions.

The menu can contain functions for:

• Fractions
• Absolute value
• Cube roots
• Roots
• Calculus functions
• Number operations
• Other mathematical commands

Example: absolute value

To calculate |−12|:

1. Press MATH.
2. Select the absolute value function.
3. Enter −12.
4. Close the parentheses if required.
5. Press ENTER.

The result is 12.

23. APPS Button

The APPS button opens applications installed on the calculator.

Applications can provide additional functions beyond the standard home-screen calculator.

Depending on the calculator model and installed software, applications can support subjects such as:

• Mathematics
• Statistics
• Finance
• Graphing
• Data analysis

Select an application with the arrow buttons and press ENTER to open it.

24. PRGM Button

The PRGM button opens the calculator's programming menu.

Users can create programs that perform repeated calculations or automate calculator operations.

To access programs

1. Press PRGM.
2. Select a program from the list.
3. Press ENTER.
4. Select the appropriate option.
5. Follow the instructions displayed on the screen.

Programs are useful when the same sequence of calculations must be performed repeatedly.

25. VARS Button

The VARS button provides access to stored variables and other calculator information.

It can be used when working with values that have been stored in the calculator.

For example, if you store a number in a variable, you can recall that value later without typing the number again.

26. Y= Button

The Y= button opens the graphing equation editor.

This is where you enter equations that you want the TI-84 to graph.

How to enter a graphing equation

1. Press Y=.
2. Place the cursor next to Y1.
3. Enter the equation.
4. Press GRAPH.

For example, to graph:

y = x²

Enter X using the calculator's X,T,θ,n button.

Then press GRAPH.

The calculator displays the graph based on the current window settings.

27. GRAPH Button

The GRAPH button displays the graph of the equations entered in the Y= menu.

How to graph an equation

1. Press Y=.
2. Enter an equation.
3. Press GRAPH.
4. Wait for the graph to appear.

Use the arrow buttons to move around the graph.

28. WINDOW Button

The WINDOW button controls the visible graphing area.

Important settings include:

• Xmin
• Xmax
• Xscl
• Ymin
• Ymax
• Yscl

How to change the graph window

1. Press WINDOW.
2. Select the value you want to change.
3. Enter the new value.
4. Press ENTER.
5. Press GRAPH.

For example, increasing Xmax allows the graph to display a larger positive x-axis range.

29. ZOOM Button

The ZOOM button provides predefined graph viewing options.

Common options include:

• Zoom Standard
• Zoom In
• Zoom Out
• Zoom Fit
• Zoom Square
• Other graph-specific views

How to zoom in

1. Press ZOOM.
2. Select the zoom-in option.
3. Press ENTER.
4. Move the cursor to the area you want to enlarge.
5. Press ENTER.

30. TRACE Button

The TRACE button allows you to move along a graphed function and view coordinates.

How to trace a graph

1. Enter an equation in Y=.
2. Press GRAPH.
3. Press TRACE.
4. Use the left and right arrow buttons.
5. Read the x and y coordinates displayed on the screen.

TRACE is useful for identifying approximate values from a graph.

31. TABLE Button

The TABLE function displays values generated by graphing equations.

How to view a table

1. Enter an equation in Y=.
2. Press 2nd.
3. Select TABLE.
4. Use the arrow buttons to move through the table.

The calculator displays corresponding x and y values.

32. TABLE SET Button

TABLE SET controls how the table generates values.

You can change settings such as:

• Starting value
• Increment
• Automatic or manual table generation

How to change the table settings

1. Press 2nd.
2. Press the button assigned to TBLSET.
3. Change the desired settings.
4. Press ENTER.
5. Open the table to view the results.

33. MATRIX Functions

TI-84 calculators can perform matrix operations.

Matrix functions can be accessed through the appropriate matrix menu, generally using the 2nd function and MATRIX key.

You can create matrices and perform operations such as:

• Addition
• Subtraction
• Multiplication
• Determinants
• Inverses
• Transposes

Basic matrix workflow

1. Open the matrix menu.
2. Select the matrix you want to create or edit.
3. Choose the matrix dimensions.
4. Enter the matrix values.
5. Return to the home screen.
6. Insert the matrix into an expression.
7. Press ENTER.

Matrix calculations are commonly used in algebra, precalculus, linear algebra, and other mathematics courses.

34. FRACTION Functions

TI-84 calculators can work with fractions through their fraction-related functions.

Entering a fraction

On supported TI-84 models and operating systems:

1. Open the appropriate fraction template or function.
2. Enter the numerator.
3. Move to the denominator.
4. Enter the denominator.
5. Press ENTER.

You can also convert between decimal and fraction forms when the calculator and expression support the required conversion.

35. STO→ Button

The STO→ button stores a value in a variable.

Example

To store 25 in A:

1. Enter 25.
2. Press STO→.
3. Press ALPHA.
4. Select A.
5. Press ENTER.

The value 25 is now stored in variable A.

You can recall the value later by entering A.

36. Ans Button

The ANS function recalls the previous answer.

Example

Suppose you calculate:

25 × 4

The answer is 100.

Now enter:

ANS + 20

The calculator uses 100 as the value of ANS.

This saves time when performing calculations that depend on a previous result.

37. How to Use the TI-84 Button System Correctly

The easiest way to understand the TI-84 is to remember that many buttons have multiple functions.

Use this basic process:

1. Look at the main label on the button.
2. Check whether another function is printed above the button.
3. Use the main button for the primary function.
4. Press 2nd first for the secondary function.
5. Press ALPHA first when entering a letter or alpha character.
6. Use arrow buttons to move through menus and expressions.
7. Press ENTER to confirm or calculate.
8. Use CLEAR to remove the current entry.
9. Use DEL to remove individual characters.
10. Check MODE before calculations involving degrees, radians, notation, or graphing modes.

38. Common TI-84 Button Mistakes

Several button errors can produce unexpected answers.

Wrong angle mode

A trigonometric calculation can produce the wrong result if the calculator is set to radians instead of degrees.

Check MODE before using SIN, COS, or TAN.

Using subtraction instead of the negative key

Use the (-) button when entering a negative number.

For example:

(-) 5

represents negative five.

The subtraction button is used to subtract one value from another.

Forgetting parentheses

Parentheses are important for complex expressions.

For example, use parentheses when you need the calculator to evaluate a complete numerator or denominator before performing another operation.

Confusing 2nd with ALPHA

2nd activates secondary functions.

ALPHA activates letters and alpha characters.

Using the wrong key can produce a different command from the one you intended.

Confusing CLEAR with calculator reset

CLEAR normally removes the current entry or clears a screen. It does not mean that the calculator has been completely reset.

A reset can affect stored data and settings, so it should be performed only when necessary.

39. Quick TI-84 Button Function Reference

Button	Main Function
ON	Turn calculator on
2nd	Access secondary functions
ALPHA	Enter letters and alpha characters
ENTER	Calculate or confirm
CLEAR	Clear current entry or screen
DEL	Delete characters
+	Addition
−	Subtraction
×	Multiplication
÷	Division
(-)	Enter a negative number
x²	Square a number
^	Raise a number to a power
x⁻¹	Reciprocal
LOG	Base-10 logarithm
LN	Natural logarithm
SIN	Sine
COS	Cosine
TAN	Tangent
MODE	Change calculator settings
MATH	Mathematical functions
STAT	Statistics
Y=	Enter graph equations
WINDOW	Set graph window
ZOOM	Change graph view
TRACE	Trace graph coordinates
GRAPH	Display graph
PRGM	Access programs
APPS	Open applications
VARS	Access variables
STO→	Store a value
2nd + appropriate key	Access secondary function

40. Final Tips for Using TI-84 Buttons

Start with the home screen when you need basic arithmetic. Use the MATH, STAT, Y=, WINDOW, ZOOM, and other menus when you need specialized functions.

Check the secondary labels above buttons whenever you cannot find a function. Many important TI-84 functions are accessed with 2nd.

Check the calculator mode before using trigonometric functions or graphing features. Use the arrow buttons to edit expressions instead of deleting the entire calculation.

Practice the most frequently used functions first. These usually include arithmetic, fractions, powers, square roots, logarithms, trigonometric functions, graphing, statistics, and variables.

The TI-84 becomes easier to use when you understand the relationship between the primary button, 2nd functions, ALPHA functions, and the calculator menus. Once these controls are familiar, you can use the same button system for algebra, geometry, precalculus, statistics, matrix operations, and graphing.