How to Use Matrices on a TI-84

Store matrix data once, then perform multiplication, determinant and inverse operations.

1Create and edit a matrix

2Perform matrix operations

3Recognize non-invertible matrices

Worked example

Follow the example values and compare your calculator display with the expected result shown below.

Create matrix [A]

2nd→x⁻¹ (MATRIX)→EDIT→1:[A]

Set the dimensions to 2 × 2, then enter:

[A] = [ 1  2 ]
      [ 3  4 ]

Multiply by another matrix

Create [B] with compatible dimensions. On the home screen, paste [A], press multiplication, paste [B], then ENTER. For A×B, the number of columns in A must equal the number of rows in B.

Calculate the determinant

Use MATRIX → MATH → det(, paste [A], close the parenthesis and press ENTER.

For [A]: det(A) = 1×4 - 2×3 = -2.

Find the inverse

Paste [A] on the home screen and press x⁻¹.

[A]⁻¹ = [ -2    1  ]
        [ 1.5  -0.5]

ERR: SINGULAR MAT: the determinant is zero, so the matrix has no inverse.

Practice

Find the determinant of [[2,1],[5,3]]. Is the matrix invertible?

Reveal the answer

det = 2×3 - 1×5 = 1. Because the determinant is nonzero, the matrix is invertible.

Practice with the calculator open

Use the guide in one tab and the calculator in another.

Open TI-84 Calculator

Editorial note: This guide is independently written for classroom practice and was reviewed against the TI-84 Plus CE guidebook. Button labels and menu availability can vary by model and operating-system version.

Last reviewed: July 17, 2026

Learning standard: worked example, expected result, troubleshooting and practice.

Matrices on a TI-84