Step Two
Now that you have identified the shape of the base you can find the area of the base. Use your formulas for two-dimensional figures. The most common formulas are:
Rectangle: A = bh or A = lw
Triangle: A = 1/2bh
Square: A = b^2 or bh
The area of the base is represented by a capital B.
Step Three
Find the height of the prism. The height of a prism is the distance between the two bases. See the picture below that shows the height of prisms.
