To find the perimeter of a rectangle using the formula \( P = 2l + 2w \), you need both the length \( l \) and the width \( w \).
You mentioned that one side is 5 cm, but you didn't specify whether this is the length or the width. Regardless, let's assume one side, which we will take as the width \( w \), is 5 cm.
Now we need to know or choose a value for the length \( l \). If we denote the length as \( l \), the perimeter can then be calculated as follows:
\[ P = 2l + 2w \]
Substituting \( w = 5 \) cm into the equation gives:
\[ P = 2l + 2(5) \] \[ P = 2l + 10 \]
Thus, the perimeter will depend on the value of \( l \). If you provide the length, the perimeter can be calculated accordingly. If you have a specific length in mind, please let me know!