Now we find out the area of the triangular side. Suppose its height will be 5 m. Therefore, the area will be 25 m2 (we multiply the length of the base by height and divide by 2). We multiply by the same cosine 30 ° and we get approximately 22 m2. Thus, the area will be 26*2+22*2, that is, 96 m2. To this number it is necessary to add about 10% of the marriage reserve.