SOLUTION: How many lines can be drawn through four coplanar points,no three of which are collunear

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Question 977217: How many lines can be drawn through four coplanar points,no three of which are collunear
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
to draw lines u have to select 2 points at a time (as no 3 are collinear)
thus number of selections of such points is:

nC2=+n%21%2F+%28+2%21+%28n-2%29%21%29....since you have 4 points, n=4, and we have
4C2=+4%21%2F+%28+2%21+%284-2%29%21%29
4C2=+4%21%2F+%28+2%21+%282%29%21%29
4C2=+%284%2A3%2A2%2A1%29%2F+%28+2%2A1+%282%2A1%29%29
4C2=+%284%2A6%29%2F+4
4C2=+6