Explanation:
Definition:
A pyramid is a polyhedron formed by connecting a one polygonal base and a point, called the apex. Each base edge and apex form a triangle.
A) A pyramid has only one base. TRUE (definition)
(look at any photo with the pyramid)
B) The base of a pyramid is a polygon. TRUE (definition)
(look at any photo with the pyramid)
C) If the altitude of a right pyramid and the apothem of the base are known, then the Pythagorean theorem can be used to find its slant height. TRUE
(look at the picture)
D) The slant height is always the same length as the base of the pyramid.
FALSE
E) The lateral faces of a pyramid are rectangles. FALSE (definition)
(the lateral faces of a pyramid always are triangles)
F) The slant height is used to calculate the lateral area. TRUE
(the lateral faces of a pyramid are triangles. The formula of an area of a triangle is A = (bh)/2. Where b - base of triangle, h - height of triangle)