We know from historical records that the Great Pyramid of Giza was originally about 147 m tall. Assuming it was built with its faces at 52 degrees inclines, what was the original length of one side of its base? Round your answer to the nearest meter
a. 91 m
b. 115 m
c. 181 m
d. 230 m
AAAaannndd the bot gets it wrong yet again!
the formula is wrong, and 239.5 does NOT round to 230!
If the bases have length 2x, then
147/x = tan52°
x = 114.84
so 2x = 229.69, or 230
The formula to use in this problem is:
Length of one side of the base = height of pyramid / (cosine of the angle of inclination)
Length of one side of the base = 147 / (cos 52°)
Using a calculator, cosine of 52 degrees is 0.614
Length of one side of the base = 147 / 0.614
Length of one side of the base ≈ 239.5 meters
Rounding to the nearest meter, the answer is d. 230 m.