Lesson 6: Solve Perimeter and Area Problems

Property

The perimeter of a rectangle is calculated using the formula $P = 2 \times (l + w)$, where $l$ is the length and $w$ is the width.
To find an unknown side length (e.g., width $w$) when the perimeter $P$ and length $l$ are known, you can use the formula:

Examples

Property

The area ($A$) of a rectangle is the product of its length ($l$) and width ($w$), calculated with the formula $A = l \times w$. To find a missing side length when the area is known, you can rearrange this formula using division: $l = \frac{A}{w}$ or $w = \frac{A}{l}$.

Examples