Question 486760

To form a triangle we have to choose only 3 points in a plane but, these must not 

collinear. So, firstly we will find total no. of ways to select 3 points from 12 

points and then subtract the number of triangle that will form by using only 5 

collinear points.  


12C3 - 5C3 = 220- 10 = 210


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