Geometry
posted by JOY on .
Determine the slant height of a right pyramid whose lateral area is 90 ft^2 and whose base is a regular hexagon with a 3 ft side.

The lateral area of a pyramid can be calculated by the following formula:
Area, A = pa/2
p=permimeter of the base polygon
a=apothem of the pyramid, i.e. the slant height.
Therefore, the slant height (or the apothem, a) can be calculated as follows:
a = 2*lateral area/perimeter of base
= 2A/p 
How do I find the perimeter of base
is it 18 
Yes, 18 is correct.
A hexagon has 6 sides, each of length 3 ft. So
Perimeter, p = 6*3 ft = 18 ft.