There are multiple possible answers for this. To determine one of the possible answers you would use the formula P = 2<em>l</em> + 2<em>w</em>, where <em>l</em> stands for the length and <em>w</em> stands for the width. I would choose a number for the length, such as a 4 and substitute it in the formula. This would make it 15 = 8 + 2w. Solve the equation by subtracting 8 from both sides and then dividing both sides by 2. This would give you a width of 3.5 units.
