Parenthesis — Definition, Formula & Examples
Parentheses are the curved symbols ( ) used in math to group parts of an expression together. Whatever is inside the parentheses gets calculated first.
Parentheses are punctuation marks that denote a grouped sub-expression within a larger mathematical expression, indicating that the enclosed operations take precedence and must be evaluated before operations outside the grouping.
How It Works
When you see parentheses in a math problem, always solve what is inside them first. This is the "P" in the order-of-operations rule PEMDAS. If parentheses are nested inside other parentheses, start with the innermost pair and work outward. Parentheses can change the result of a calculation entirely by overriding the normal order of operations.
Worked Example
Problem: Solve 3 × (4 + 2).
Step 1: Look inside the parentheses and solve that part first.
Step 2: Now multiply by 3.
Answer: The answer is 18. Without parentheses, 3 × 4 + 2 would equal 14 instead, because multiplication would happen before addition.
Why It Matters
Parentheses are essential whenever you write or read a math expression, from basic arithmetic through algebra and beyond. Misplacing or forgetting parentheses is one of the most common sources of wrong answers on homework and tests.
Common Mistakes
Mistake: Ignoring parentheses and just solving left to right.
Correction: Always evaluate what is inside parentheses first. For example, in 5 + (3 × 2), compute 3 × 2 = 6 first, then add 5 to get 11.