Constant vs Variable Math Example 1

Solution

1. 1
   $\pi \approx 3.14159$ is a constant—it never changes.
2. 2
   $2$ is a constant coefficient.
3. 3
   $r$ (radius) is a variable—it can be any positive number.
4. 4
   $C$ (circumference) is a variable—it depends on $r$.