Math basics › Numbers and fractions
Order of operations
The order
Brackets, then exponents and roots, then × and ÷ together left to right, then + and − together left to right.
The part people get wrong
× and ÷ share a rank, and so do + and −. 8 ÷ 4 × 2 is 4, not 1: you go left to right, not division first.
A minus sign in front of a square
−x² means −(x²). To square the negative you need (−x)². These are different numbers and it matters.