The area of a square piece of cardboard is 81 square inches. What is the length of the cardboard? A. 10 inches B. 9 inches C. 8 inches D. 20.25 inches

Respuesta :

The answer is B. 9 inches  because a square has 4 equal sides. The area of a square equals length times width...

So that means all 4 sides are 9 inches

9x9=81