Area of a rectangle is 42 sq inches and one side is 12 inches long what is the perimeter of the rectangle?

Area if the rectangle = 42 sq. inch
Area of a rectangle = l × b
42 = 12 × b
b = 42/12 = 3.5 inch
Now, perimeter of a rectangle= 2(l + b)
= 2(12+3.5) = 2(15.5) = 31 inches