Shormann Algebra 1 Rules & Definitions Quarterly Exam 1 Practice

Area is the amount of surface a shape covers. For a rectangle, imagine tiling it with unit squares. If the length is L units and the width is W units, you can lay out L rows each of W squares, or W columns each of L squares. Counting all those unit squares gives L × W square units. So the area of a rectangle is the product of its length and width.

The other expressions don’t measure surface area in the rectangle sense: adding the sides would give a length, not an area; splitting the product in half is used for a triangle’s area; and πr^2 is the circle area formula.