Question 22
The two lines shown have 7 points and 6 points respectively. How many triangles can be formed using any three of the marked points as vertices?
Editorial clarification of the source wording: choose any three distinct marked points among all 13; the unmarked intersection of the extended lines is not an available vertex.
Editorial clarification of the source wording: choose any three distinct marked points among all 13; the unmarked intersection of the extended lines is not an available vertex.