The TI-84 Calculator can calculate square roots in a few button presses. The square root function is useful for algebra, geometry, statistics, physics, and other math problems. You can calculate the square root of a whole number, decimal, fraction, or mathematical expression.

The TI-84 Calculator displays exact results when possible and can also show decimal approximations. The method is similar across common TI-84 models, including the TI-84 Plus and TI-84 Plus CE.

How to Enter a Square Root on a TI-84

Follow these steps to calculate a basic square root.

  1. Turn on your TI-84 Calculator by pressing the ON button.
  2. Press the 2nd button.
  3. Press the xยฒ button.
  4. The calculator will insert the square root symbol, โˆš(.
  5. Enter the number you want to calculate.
  6. Press the ) button if needed.
  7. Press ENTER.

For example, to calculate โˆš25:

Press: 2nd โ†’ xยฒ โ†’ 25 โ†’ ) โ†’ ENTER

The calculator returns:

5

The xยฒ button has two functions. The primary function calculates the square of a number. The secondary function, accessed with 2nd, opens the square root function.

How to Calculate the Square Root of a Decimal

The TI-84 can also calculate square roots of decimal numbers.

For example, to calculate โˆš12.25:

  1. Press 2nd.
  2. Press xยฒ.
  3. Enter 12.25.
  4. Press ).
  5. Press ENTER.

The result is:

3.5

If the result is not a whole number, the TI-84 may display a decimal approximation depending on the calculator settings.

How to Find the Square Root of a Fraction

You can enter a fraction inside the square root symbol.

For example, to calculate โˆš(9/16):

  1. Press 2nd.
  2. Press xยฒ.
  3. Enter the fraction.
  4. Close the square root expression.
  5. Press ENTER.

The result is:

0.75

You can also use the MATH menu to work with fractions and other mathematical expressions.

How to Find the Square Root of an Expression

The square root function can include a complete mathematical expression.

For example, you can calculate:

โˆš(16 + 9)

Enter the square root symbol first. Then enter 16 + 9 inside the parentheses. Press ENTER to calculate the result.

The TI-84 first evaluates the expression inside the square root. The answer is:

5

This method is useful when a square root problem contains multiple operations.

How to Enter a Square Root in an Equation

You can also use the square root function when solving equations manually.

For example:

xยฒ = 49

The square root of 49 is 7. However, remember that the original equation has two solutions:

x = 7 and x = -7

The square root function itself returns the principal square root, which is the nonnegative value.

What If the TI-84 Shows an Error?

A square root can produce an error when you enter an invalid expression.

For example, the square root of a negative number produces a DOMAIN ERROR when the calculator is operating in real-number mode.

Check the following if you receive an error:

  • Make sure the number or expression is entered correctly.
  • Check that parentheses are balanced.
  • Make sure you are using the correct calculator mode.
  • Press CLEAR and enter the expression again.

For complex-number calculations, the TI-84 can work with complex values when the appropriate mode and syntax are used.

How to Get a Decimal Answer

If the TI-84 displays an exact or fractional result and you want a decimal approximation, press MATH and select the appropriate decimal conversion option when available. You can also use the calculator's decimal conversion functions for supported expressions.

For most basic square root calculations, entering the expression and pressing ENTER is enough.

Key Points to Remember

The fastest way to enter a square root on a TI-84 is:

2nd โ†’ xยฒ

Then enter the number or expression inside the square root.

For example:

โˆš36 = 6

โˆš81 = 9

โˆš144 = 12

The TI-84 Calculator makes square root calculations simple once you know the location of the function.