Solve this problem (Solid Geometry)

A prism has an equilateral triangle with 20 cm on a side for its base, and an altitude of 30 cm. Determine its lateral area.

Lateral area on a prism is simply the rectangles that make up the long sides. To find the area of all the rectangles, you multiply the perimeter of the base x the height of the prism. Picture the prism taken apart - the sides would look like one big rectangle, and the length of the rectangle is the perimeter of the base.

If the base is 20 cm per side, the perimeter of the base is 60. The height of the prism is 30. 60 x 30 = 1800 sq. cm.

A=area of equilateral triangle with 20 cm on a side
A^2= 30(30-20)(30-20)(30-20)
=30*10*10*10
=30000
A=173.21
ateral area.= 2A+ (20+20+20)*30
=2*173.21+ 60*30
= 1800+346.41
=2146.41cm^2