In today's Science section....
How many triangles are formed by six intersecting lines? Given that no two lines are parallel, and there are no points where more than two lines intersect.
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In today's Science section....
How many triangles are formed by six intersecting lines? Given that no two lines are parallel, and there are no points where more than two lines intersect.
For each of the six lines, every one of the five (non-parallel) lines crosses exactly once. For each of those pair of lines each of the four remaining lines must cross to form a triangle. That defines 6×5×4=120 line combinations that form triangles, but does not take into account that abc, bac, cba, etc are the same triangle. There are 3×2×1=6 such ways to describe each triangle, so there are 120/6=20 unique triangles. There is a fancy mathematical way to write this, but I forget how.
it's actually the point of a pin and the answer is 8.6766×10exp49
https://improbable.com/airchives/pap...angels-7-3.htm
20 is the answer....
It depends on the angles between the angels.