LearnViz Math
Advanced ▦ Linear Algebra Topic 20 of 104

Linear Systems as Matrices

Write simultaneous equations as Ax = b.

Key idea

Write simultaneous equations as Ax = b.

In depth

A system of linear equations is Ax = b: A holds the coefficients, x the unknowns, b the right sides. Matrix language handles any number of equations and variables at once.

Worked example

2x + y = 5, x − y = 1 becomes [2 1; 1 −1][x; y] = [5; 1].

Formula

Ax = b

Real-world uses

Common mistake

Writing coefficients in inconsistent order of variables.

How to learn this

  1. Read the key idea and say it in your own words.
  2. Work through the worked example, then try a similar problem.
  3. Use the interactive lesson’s visual and mini-quiz to check the pattern.

Frequently asked questions

What is Linear Systems as Matrices?

Write simultaneous equations as Ax = b. It is a topic at the advanced level in Linear Algebra.

What is the formula for Linear Systems as Matrices?

The key formula is Ax = b.

Where is Linear Systems as Matrices used in real life?

Real-world examples: Solving mixing problems such as blending fuels with set properties in a single matrix equation.

What should I learn before Linear Systems as Matrices?

Make sure you are comfortable with Special Matrices, the previous topic in Linear Algebra.

What is a common mistake with Linear Systems as Matrices?

Writing coefficients in inconsistent order of variables.

How can I practise Linear Systems as Matrices?

Open the interactive lesson, play with the visual, then answer the three-question mini-quiz. Getting two right marks the topic complete.

What comes after Linear Systems as Matrices?

Move on to Augmented Matrix next.

Related advanced topics in Linear Algebra