Collecting like terms means to simplify terms in expressions in which the variables are the same. In the expression \(5a + 2b + 3a - 6b\), the terms \(5a\) and \(+ 3a\) are like terms, as are \(2b\) ...

A mathematical proof is a sequence of statements that follow on logically from each other that shows that something is always true. Using letters to stand for numbers means that we can make statements ...