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jwxie
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Homework Statement
A regular tetrahedron has the vertices of its base A(1,1,0) B(3,1,0) C(2,1+(3^(1/2),0). Find coordinate of vertex S?
Homework Equations
The Attempt at a Solution
If this is a tetrahedron
Then we know the length by caclulating the distance formula, which gives length of 2.
My game plan is to find the height in order to determine the z-coordinate.
I thought I could just get length of the apothem, which is given by a = [sqrt(3)/6]*s, where s is 2 in this case. this gives us sqrt(3)/3
Then I tried to calculate the length of BH... so (sqrt(3)/3))^2 + (1)^2 = BH^2
and i have BH = 2/sqrt(3), or 2*sqrt(3)/3
anyway. this leads to caclulate the height AOH, and i had [2/sqrt(3)]^2 + (2)^2 = AOH^2, where 2^2 comes from the length of AB...
and AOH is 4/sqrt(3)
I don't have any solution to this problem, but upon googling someone attempted the problem.
http://answers.yahoo.com/question/index?qid=20100903153810AAmVNTY
I am not sure where I did wrong, if that solution is corrected.
Just by looking at the z-value, I would have 4/sqrt(3)... which is different from whatever was solved on yahoo answer.
Can anyone please help me on this? Thanks!