6.2 – Surface Areas of Prisms and Cylinders

Definitions Prisms A polyhedron with 2 congruent, parallel bases.

Types of Prisms Prisms are named for the shapes of their bases.

Definitions Lateral Faces Lateral Area Surface Area The faces on the prism except for the parallel bases. Lateral Area The area of all of the rectangles on the outside of the prism. LA = P x H (perimeter of base x height) Surface Area The lateral area plus the area of the 2 bases. SA = LA + 2B (lateral area + area of both bases)

Example 1 Find the surface area of the prism. Lateral Area Area of 3 rectangles (3+4+5)6 = 72 Area of bases each triangle Total Surface Area Area of 3 rectangles + 2 triangles 72 + 6 + 6 = 84

Example 2: Cylinder Find the lateral area and surface area of a cylinder with a radius of 4in. and a height of 6in. Lateral Area = Perimeter (circumference) times the height. Surface Area = LA + 2B