Find the inverse of a matrix if it exists and use it to solve
systems of linear equations (using technology for matrices of
dimension 3 × 3 or greater)

### Suggested Learning Targets

- Write a system of linear equations as a single matrix
equation.
- Find the inverse of the coefficient matrix in the equation, if
it exits. Use the inverse of the coefficient matrix to solve the
system. Use technology for matrices with dimensions 3 by 3 or
greater.

Common Core: HSA-REI.C.8, HSA-REI.C.9

Using a Matrix Equation to Solve a System of Equations

This video shows how to solve a system of equations by using a
matrix equation. The graphing calculator is integrated into the
lesson.

Ex 1: Solve a System of Two Equations Using a Matrix Equation

This video explains how to solve a system of two linear equations
with two unknowns using a matrix equation.

Ex 2: Solve a System of Two Equations Using a Matrix Equation

This video explains how to solve a system of two linear equations
with two unknowns using a matrix equation.

Matrices to solve a system of equations

Using the inverse of a matrix to solve a system of equations.

Ex: Solve a System of Three Equations Using a Matrix Equation

This video explains how to solve a system of three linear equations
with three unknowns using a matrix equation. Use a calculator to
find the inverse of the 3 × 3 matrix.

Solve a 3 variable system with a matrix in the calculator.

## Matrix Calculator

### 3×3 Inverse Matrix Calculator

Enter in your 3×3 matrix to get the inverse.

### 4×4 Matrix Multiplication

Enter in the two 4×4 matrices that you want to multiply

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