The Great pyramid of Giza has a square base with side length 755 ft. and original height of 481 ft. Determine its surface area. The answer is 923,285 ft. But i don't know how to get that answer. Please help.
The surface of pyramid is calculated by summing surface of its base and surface of its mantle.
Surface of base is easy to calculate. You have a square and its side is known therefore surface is: Sb = a^2 Surface of mantle is a bit more complicated to calculate. First you have 4 sides of pyramid and each side is a triangle. To calculate surface of each triangle we need to know its height. First we calculate side of triangle using Pitagorah's theorem. s = √((d/2)^2 + H^2) where d is diagonal of base which is square. d = √2*a
Now again we have to use Pitagorah's theorem to calculate height of the triangle. h = √(s^2 - (a/2)^2)
Now the surface of the triangle is calculated with: St = (a*h)/2 and surface of mentle is: Sm = 4*St.
