Answer:
Why isn't there a picture-
Step-by-step explanation:
HEHEH BOIS
Because in an equilateral triangle all angles should measure 60 degrees otherwise all sides would not be equal.
1st element can be matched with 5
2nd element can be matched with 4
3rd element can be matched with 3
etc.
Total number of correspondences = 5*4*3*2*1 = 120