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Sun 24 Sep, 2006 08:10 pm
This question was a part of another post I made here, but this assignment is due tomorrow (Monday) at 4:00 Eastern Standard time and I did not understand the explanation given by another member on the board.
If someone could go through each step (providing numbers and equations) I would very much appreciate it!
THANK YOU!
2. A regular hexagon with edges of length 12 cm is the base of a pyramid. The combined area of the lateral faces of the pyramid is 480 square cm.
a) What is the volume of the pyramid.
b) To the nearest tenth of a degree, calculate the size of the dihedral angle formed by the hexagonal base and a lateral face of the pyramid.
This sounds like a trig problem. Is it?
vol=1/3 base area x height
You have the area, which is 480 square cm, now you have to calculate the height, inside using the same method you would use to calculate the height of a triangle. (Pythagoras equation ).
Now draw a little diagram, and you'll see that you'll have to use again, the pathagoras relationship to determine the angle of the triangular segment formed between the face of the segment and the base of the pyramid.
I hope this helps. I used to be an A student in trig, but I haven't used this math in many, many years.
One piece of advice, is to always draw a diagram to fully explain the word problem. Also you need to use the correct
dimensions. For solids, the abbreviation is cm3 not cc , as
cc is used ONLY for liquids.
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