Parentheses First
Part of the Numbers & Operations section of Coddy's Pre-Algebra journey. Lesson 9 of 60.
Parentheses change the order on purpose. Whatever is inside them is worked out first, before anything else in the line. Compare 2 + 3 × 4, which is 14, with (2 + 3) × 4: the parentheses say to add first, so it is 5 × 4, which is 20.
Think of parentheses as a package: the line asks for the value of the package, so you have to open it before you can use it. The rest of the rules then apply as usual.
Parentheses are how you write the meaning you intend. If you want 2 and 3 added before the multiplication, you must write the parentheses; without them, the reader multiplies first.
Challenge
Work out (9 - 4) × 6.
Try it yourself
Simplify the expression
Test yourselfThis lesson includes a short quiz. Start the lesson to answer it and track your progress.
All lessons in Numbers & Operations
1Working on the Board
Your First AnswerType the Next LineOne Line at a TimeDots and BarsFriendly ProductsRecap: Board Work4Adding Integers
Adding Two NegativesDifferent SignsZero PairsAdding Several IntegersRecap: Adding Integers2Order of Operations
Multiply Before AddingLeft to RightParentheses FirstBrackets Inside BracketsThe Fraction Bar GroupsRecap: Order of Operations5Subtracting Integers
Add the OppositeSubtracting a NegativePlus and Minus in a RowDistance Between NumbersRecap: Subtracting Integers