Wikipedia says: "The apothem of a regular polygon is a line segment from the center to the midpoint of one of its sides. Equivalently, it is the line drawn from the center of the polygon that is perpendicular to one of its sides. The word "apothem" can also refer to the length of that line segment. Regular polygons are the only polygons that have apothems. Because of this, all the apothems in a polygon are be congruent".
The Figure shows a regular hexagonal pyramid, an apothem of the regular hexagon in its base (OP), the pyramid's height (RO) and its slant height (RP). The length of the apothem OP is given: |OP| = 8 cm. We also know that the length of the lateral edge is twice the base edge length: |AR| = 2*|AB|. The apothem OP is the height of the regular triangle Therefore, |OP| = Since the length of the lateral edge is twice the base edge length, we have |AR| = 2*|AB| = 2* Now from the right-angled triangle |OR| = |
Regular hexagonal pyramid, its height and a slant height. |