SOLUTION: Kyle connected four noncoplanar and noncollinear points. How many lines and planes are formed ?

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Question 1050578: Kyle connected four noncoplanar and noncollinear points. How many lines and planes are formed ?
Answer by ikleyn(52776) About Me  (Show Source):
You can put this solution on YOUR website!
.
%284%2A3%29%2F2 = 6.

Each pair of points determines one line, a unique line.

So, the number of lines is equal to the number of pairs of points.

The number of pairs taken from the set of 4 points, is the number of combinations
of four points taken 2 at a time: C%5B4%5D%5E2 = %284%2A3%29%2F2 = 6.
On combinations, see the lessons
    - Introduction to Combinations
    - PROOF of the formula on the number of Combinations
    - Problems on Combinations
in this site.