Evaluate in this exact order: P → E → M/D → A/S Parentheses · Exponents · Multiply & Divide (L→R) · Add & Subtract (L→R)

Same signs → Add, keep sign.   Different signs → Subtract, keep sign of larger |value|. −5 + (−3) = −8  |  −5 + 3 = −2

To add fractions: find LCD, convert, then add numerators. a/b + c/d = (ad + bc) / bd

aⁿ = a multiplied by itself n times. √a = number that squares to a. 2³ = 8  |  √49 = 7

Isolate the variable by performing inverse operations on both sides. 2x + 3 = 11 → 2x = 8 → x = 4

Proportion: a/b = c/d → ad = bc (cross multiply). % of n = (percent / 100) × n

Distributive Property: a(b + c) = ab + ac
Combine Like Terms: add/subtract same variable terms. 3(x + 4) = 3x + 12  |  5x + 3x = 8x

Solve like an equation, but flip the inequality sign when multiplying or dividing by a negative number. 3x < 12 → x < 4

Quadrants: I(+,+) II(−,+) III(−,−) IV(+,−) starting top-right, going counter-clockwise. slope m = (y₂ − y₁) / (x₂ − x₁)

Area of rectangle = l × w  |  Perimeter of square = 4s
Scientific notation: a × 10ⁿ where 1 ≤ a < 10. 3,400 = 3.4 × 10³