Final answer:
There are 505 possible triangles that can be formed using the marked points on the sides of triangle ABC.
Step-by-step explanation:
To find the number of triangles that can be formed using the marked points on the sides of triangle ABC, we need to consider the possible combinations of three points.
For the first side with 10 marked points, there are 10 choose 3 combinations, which can be calculated as C(10,3) = 120.
Similarly, for the second side with 11 marked points, there are C(11,3) = 165 combinations, and for the third side with 12 marked points, there are C(12,3) = 220 combinations.
Adding the three combinations together, we get 120 + 165 + 220 = 505. Therefore, there are 505 possible triangles that can be formed using the marked points.