60cibu wrote:My question is as follows:  Stonehenge required 550 people to pull a single stone up a ramp inclined at a 9° angle.  Describe how right triangle trigonometry can be used to determine the distance the 550 workers had to drag a stone in order to raise it to a height of 30 feet.  Does anyone know how to convert this 9° to a measurement of length or at least tell me what this formula is and how it works?  I understand that it must be based on the Pythagoren Theorem which involves the use of right triangle trigonometry.
How the stones were raised at Stonehenge is theoretical but it does make sense to use an earthen ramp and that is where the evidence points, however, to answer your question . . . 
Using trigonometry with a right triangle.  The 30 ft height is the opposite side of Theta (9º).  The formula is: Opposite side / SIN(Theta) = the hypotenuse (the ramp), so: 30 / SIN(9) = 30 / 0.156434465040 = 191.77 ft long ramp.
Note: The Pythagoren Theorem requires 2 sides to calculate the 3rd side