Originally Posted by
masterartill
how do you find the area of a octagon
how do you find the area of a hexagonal prism's surface area
how do your find the volume of a octagonal prism
Think of an octagon as basically a square with 4 triangles cut out of the corners. The area is therefore the area of the square minus the areas of the 4 corner triangles. The only hard part is figuring the lengths of the legs of the triangles.
Surface area of a prism would be the area of the top + area of the bottom + area of all the sides. So you need to be able to calculate the area of the hexagon son the top and bottom, which you can do by adding the areas of triangles and/or rectangles that can be put together to make up the hexagon. The side walls are simply rectangles, so finding their area is easy.
Volume of a regular prism is base area times height, regardless of the shape (octagonal, hexagonal, square, etc).