This facility allows you to quickly multiply two matrices similar to the example shown below. It is available only when you sign in to your Transum subscription account. If you do not yet have an account and you are a teacher, tutor or parent you can apply for one by completing the application form.
A Transum subscription also gives you access to the 'Class Admin' student management system, downloadable worksheets, many more teaching resources and opens up ad-free access to the Transum website for you and your pupils.
If you are still reading, I guess you are a student. Sorry this tool isn't available but you could have a go at the exercise mentioned below.