The eight-minute video above from ExamSolutions shows you how to expand brackets in an several expressions.
The ten-minute video above is the first of a two-part series that contains a great explanation of how to expand the brackets or "distribute". This is a US film, so the teacher says "parentheses" instead of "brackets", but it's such a good explanation that it's worth putting up with the US terminology.
The above video is the second of a two-part series on how to expand brackets or "distribute" in algebra. This video focuses on distributing negative signs.
There are times when you MUST use brackets to be correct.
Expanding brackets incorrectly is one of the most common errors in equation solving.
Study and practice
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the distributive property in algebra