A sketch of your pyramid is schematically shown in the Figure 1a (not in the scale, though). The base of the given pyramid is a square, of course. Draw the straight interval from the base center to the middle of the base side. Its length is 16/2 = 8 cm. Next, draw the slant height from the vertex of the pyramid to that point (Figure 1b). Find the length of the slant height from the right triangle. It is Notice that the slant height has the same length for all lateral faces of the pyramid. |
Figure 1a |
Figure 1b |