Answer: length and width
Explanation:
The most common starting point in elementary school when one is discussing the concept of area is length (longer side) and width (shorter side) of a regular size object.
Book or notebook can be the best example that does have length and width.
Suppose the length of a book cover is 10 inches and width of that book cover is 6 inches. So what is the area of that book cover?
We know Area= length X width
So area of book cover = 10 inches X 6 inches = 60 square inches ( inches X inches = square inches).
Before discussing area must have to to have knowledge about length and width.