How many distinct triangles can be drawn using three of the dots below as vertices?

Guest Jul 13, 2020

#2**+2 **

hmm I think a better approach to this problem is to use complementary counting.

There are \(\dbinom{6}{3}=20\) ways to choose 3 points to make a triangle. However **2 ** of these ways are just straight lines, so \(20-12=\boxed{18} \text{ triangles. }\)

I'm not sure if this is right, so please let me know if it's correct or not!

:)

lokiisnotdead Jul 13, 2020