(adsbygoogle = window.adsbygoogle || []).push({}); Let P_{1}, P_{2}, ..., P_{5}be five points, no three of which are collinear. How many lines contain two of these five points?

How I thought about solving this was by way of combinations.

C_{5,2}= (5*4*3*2)/2 = 60.

So there would be 60 lines that contain 2 of the 5 points. Is this a good way to approach this problem or is there a better way?

Thank you for your help!

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# Homework Help: Help with a question about collinear points

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