1. **State the problem:** We have a rectangle with width $3$ units and an unknown length $L$ units. The problem states that the perimeter and the area of the rectangle have the same numerical value. We need to find the length $L$.
2. **Recall formulas:**
- Perimeter of a rectangle: $$P = 2(\text{length} + \text{width}) = 2(L + 3)$$
- Area of a rectangle: $$A = \text{length} \times \text{width} = L \times 3 = 3L$$
3. **Set up the equation:** Since the perimeter equals the area, we have:
$$2(L + 3) = 3L$$
4. **Solve the equation:**
$$2L + 6 = 3L$$
Subtract $2L$ from both sides:
$$6 = 3L - 2L$$
$$6 = L$$
5. **Interpret the result:** The length of the rectangle is $6$ units.
**Final answer:** The length of the rectangle is $6$ units.
Rectangle Length
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