The perimeter of a shape is the total length around its boundary. The formula for calculating the perimeter depends on the type of shape you're working with. Here are some common formulas:

1. Rectangle: $P = 2 \times (l + w)$ Where:

   • $l$ = length
   • $w$ = width

2. Square: $P = 4 \times s$ Where:

   • $s$ = side length

3. Triangle: $P = a + b + c$ Where:

   • $a, b, c$ = lengths of the three sides

4. Circle (Circumference): $C = 2 \pi r$ Where:

   • $r$ = radius

5. Regular Polygon (e.g., hexagon, octagon): $P = n \times s$ Where:

   • $n$ = number of sides
   • $s$ = side length

Would you like to see a specific example? Or do you have a particular shape in mind?