Resource explains how to simplify several types of expressions that contain expressions using the properties of addition and multiplication and applying the properties with the order of operations.

Please excuse my dear Aunt Sally. This sentence takes on greater meaning when students realize it will assist them in remembering the all-important order of mathematical operations. A lesson plan, several interactive practice pages, and...

Here is a site that clearly and thoroughly explains adding like terms, including terms with signs and terms within parentheses. There are example problems solved, problems for the student to attempt, and answers to the student problems....