To find the area (not surface area because 'surface area' is measuring a 3D shape, whilst 'area' is measuring a 2D face.) of a triangle, you simply take your base and height, multiply by 2, then divide by 2 because a triangle is half of a parallelogram.
In this case, it's 11ft by 16ft. 16ft times 11ft = 176ft. Then 176ft divided by 2, which is 88.
Each triangular face has an area of 88ft. -------------------------------------- Now moving on to the square base, the dimensions are 11ft by 11ft. To find the area of a square, you multiply L(ength) times W(idth).
In this case, it's 121ft.
Now, you have 121ft as your square base, and 88ft each triangular face. The total surface area is 209ft.
