A coefficient is the number or constant factor that multiplies a variable in a mathematical expression or equation.

Quick Scoop: What is the coefficient?

Think of a coefficient as the “how many” in front of a variable.
In the term 5x5x5x, the coefficient is 5 because it tells you that you have 5 copies of xxx.
In −3xy-3xy−3xy, the coefficient is −3-3−3, and it multiplies the whole variable part xyxyxy. Some key points:

  • A coefficient is usually a number that sits directly next to a variable (like 2 in 2y2y2y or 7 in 7a27a^27a2).
  • If a variable appears with no number written, its coefficient is understood to be 1 (for example, in xxx, the coefficient of xxx is 1).
  • Coefficients can be:
    • Positive or negative numbers (like 4, −9-9−9)
    • Fractions or decimals (like 12\tfrac{1}{2}21​ in 12x\tfrac{1}{2}x21​x, or 0.3 in 0.3y0.3y0.3y)
    • Symbols/letters representing constants (like aaa and bbb in ax+byax+byax+by)

Mini example

  • In 7x2−3x+47x^{2}-3x+47x2−3x+4:
    • Coefficient of x2x^{2}x2 is 7
    • Coefficient of xxx is −3-3−3
    • 4 is a constant term, not a coefficient of a variable

If you have a specific expression (like “what is the coefficient in ………?”), send it and I’ll point out exactly which number or symbol is the coefficient. Bottom note: Information gathered from public forums or data available on the internet and portrayed here.