## Introduction: Solving a System of Linear Equations.

This instruction will help you to solve a system of 3 linear equations with 3 unknown variables.

Minimum requirements: Basic knowledge of algebra and internet access.

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## Step 1: Start.

Write down your equations in one column, so each equation is written on its own row.

## Step 2: Organize.

Step 2. Organize all equations so "x" is written first, then "y", and then "z". Transfer all constants to the right side of the equation in each row. Simplify if needed.

## Step 3: Go To....

Open website matrixcalc.org.

## Step 4: Underline.

Underline all coefficients in front of each variable including zeros.

## Step 5: Fill in Numbers.

Fill in coefficients from x, y, z to the matrix A, in order left to right and top to bottom. Don't forget to include the negative sign if the number is negative.

## Step 6: Fill in Numbers.(cont.)

Fill in constants to the first column of the matrix B, in order from the top to the bottom. Remember to include the negative sign if the number is negative.

## Step 7: Check.

Check display decimals box if you wish your answers to be displayed in decimals.

## Step 8: Fill in an Operation Line.

In the fill-in line below the matrices type A^-1*B and click equals button.

## Step 9: Get Answers

The answers will be shown below the display decimals check box. Locate the matrix on the right of the equals sign.

## Step 10: Write Down the Answers.

Write down your answers in order from the top to the bottom for x, y, and z.

## Discussions

2 years ago

Ah, linear equations. My old nemesis. Nice tutorial. Thanks for sharing it with the community.