In algebra, letters are used to stand for values that can change (variables) or for values that aren’t known (unknowns). A term is a number or letter on its own, or numbers and letters multiplied ...

Expanding brackets means multiplying everything inside the bracket by the letter or number outside the bracket. For example, in the expression \(3(m + 7)\) both \(m\) and 7 must be multiplied by 3: ...