Constant vs Variable Math Example 2

Follow the full solution, then compare it with the other examples linked below.

Example 2

medium
In the equation y=3x+5y = 3x + 5, someone says '3 is a variable because it could be any slope.' Is this correct?

Solution

  1. 1
    In this specific equation, 3 is a fixed number (the slope)—it is a constant.
  2. 2
    If we wrote y=mx+5y = mx + 5, then mm would be a parameter (a changeable constant).
  3. 3
    But in y=3x+5y = 3x + 5 as given, the 3 is a constant.

Answer

No—3 is a constant in this equation.
The distinction depends on context. In a specific equation, numerical coefficients are constants. They only become parameters when we consider a family of equations.

About Constant vs Variable

Constants are symbols with fixed, unchanging values; variables are symbols whose values can change or are yet to be determined.

Learn more about Constant vs Variable →

More Constant vs Variable Examples

Example 1 easy

In [formula], identify the constants and variables.

Example 3 easy

In [formula] (Newton's second law), which symbols are variables?

Example 4 medium

Is 0 a constant or a variable?

← All Constant vs Variable Examples Constant vs Variable Concept