Brackets group things that should be treated as one. Solve what's inside first — that's the P in PEMDAS.
Three flavours
- ( ) parentheses — innermost
- [ ] square brackets — next
- { } curly braces — outermost
Try it
2[3 + (4 × 2)]
Inner: 4×2=8. Then 3+8=11. Then 2×11=22.