Given the formula for the perimeter of a rectangle:

$P = 2L + 2W$

where:

• $P$ is the perimeter,
• $L$ is the length, and
• $W$ is the width.

You are tasked with solving for the length $L$.

Steps:

1. Start with the formula for the perimeter: $P = 2L + 2W$
2. Subtract $2W$ from both sides: $P - 2W = 2L$
3. Divide both sides by 2 to isolate $L$: $L = \frac{P - 2W}{2}$

Thus, the correct formula for the length $L$ of the rectangle is:

$L = \frac{P - 2W}{2}$

This formula allows you to compute the length when the perimeter $P$ and the width $W$ are known.

Do you have any questions or want more details?

Here are some related questions:

1. How do you derive the formula for the width if the length and perimeter are known?
2. Can this formula be applied to irregular quadrilaterals?
3. How would this formula change if only the area and one dimension are known?
4. What happens to the formula when the rectangle is a square?
5. How can you calculate the diagonal of the rectangle if the perimeter and width are known?

Tip: Always check that the calculated values for length and width make sense in the context of the given perimeter!