There are seven points on a plane such that three of the points are collinear. How many different line segments connect the points?

A) 21
B) 33
C) 42
D) 210

Question

There are seven points on a plane such that three of the points are collinear. How many different line segments connect the points?

A) 21
B) 33
C) 42
D) 210

fibonaccichick666 · Answer

well, think about the number of combinations of 3 points from a pool of 7

anonymous · Answer

I'm sorry, I don't know English very well. But what do you mean combinations?

fibonaccichick666 · Answer

that word is the Big hint

fibonaccichick666 · Answer

uhm, just google the difference between combinations and permutations

anonymous · Answer

OK, I did, but it still doesn't make sense. I kinda understand it.

fibonaccichick666 · Answer

so uhm, I really don't know how to explain without using the word combination...so do it the long way.  make a list of all the different ways you can write 3 points

anonymous · Answer

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