We first need to find the length of one side of the square. We can do this by dividing the area by 4 (27/4), since a square has four sides. You should get 6.75. Now you can multiply 6.75 by three since one side of the square is the same as one side of the triangle. Also, it is an equilateral triangle and all sides are the same. If you multiply correctly, you should get 20.25. Hope this helped!