To find the surface area, you will need to find the area of all 6 surfaces (all the faces). They are all rectangles and many of them are congruent!! To find the area of each rectangle, use the formula A = lw. The front and back have the same area (7 x 6 = 42 square cm), the two sides have an area of 36 square cm (6 x 6 = 36), and the top and bottom have an area of 49 square cm (7 x 7 = 49). Add the areas of all 6 sides together (42 + 42 + 36 + 36 + 49 +49 = 254 square cm - don't forget you label). Another way would be to take 2 x 42 + 2 x 36 + 2 x 49.