A dog weighs 20% more than it did three months ago. It weighs 36 pounds now. How much did the dog weigh three months ago?

The area of a rectangle is 10 cm^2. one side of the rectangle is x cm. express the perimeter of the rectangle in terms of x and show that this rectangle cannot have a perimeter of 12 cm. the perimeter of the rectangle in terms of x is __ cm