Question

i need help! please help

How many lines are determined by 7 points, no 3 of which are collinear? How may triangles are determined by the same points if no 4 are coplanar?

Answer 1

I don't know if there is a formula but I think there is going to be 7 points (why so big a number?) anyway
1-2, 1-3, 1-4, 1-5, 1-6, 1-7
2-1(but that is the same at 1-2 so wont count, 2-3, 2-4, 2-5, 2-6, 2-7
3-1(already accounted for), 3-2(already counted), 3-4, 3-5, 3-6, 3-7
I see a pattern emerging...