How many triangles can be drawn on a plane using 7 non-collinear points?

Sagot :

Answer: 35

Collinear can be formed by joining any three non-collinear points in pairs. there are 7 non-collinear points. The number of triangles formed

7C3

7*[7-1]*[7-2] / 3

7*6*5/ 3*2*1 = 7*5= 35