Question 549699
To find the area and perimeter of a rectangle, we need to know the width and length.  This information was not given.  

If by the letter e you mean the side of a square, then look below.

Area of square = (12cm)^2 = 12cm times 12cm = 144cm^2


Perimeter of square = 12cm times 4 = 48cm


I hope this helps.