Respuesta :

Total Surface = 5

Top and Bottom are both triangles
1/2 x 10 x 5 = 25 
25 x 2 = 50

The two sides are rectangles
6 x 8 = 48
48 x 2 = 96

The back is a rectangle
10 x 8 = 80

Total = 50 + 96 + 80 = 226 square units