If the area of this rectangle is 30cm square what would the missing side be?

The area of a rectangle is calculated with this formula: Area = Length • Width. Given the area of the rectangle, we can substitute it in for “A” (area) in the formula, so that we can solve for the missing width value.

A = L • W [Area if Rectangle Formula]

A = 30cm^2 [Given]

(30) = (6) • W [Substitution Property of

Equality]

30 / 6 = 6 • W / 6 [Division Property of

Equality]

5 = W [Definition of Equality]

W = 5 [Symmetric P.O.E]

Therefore, the width of this rectangle is 5.
We can check this because A = 6 • 5 = 30cm^2