'run' is distance x direction changes
'rise' is distance y direction changes
slope='rise'/'run'
for ABC
'run' is 11-3 or 8
'rise' is 10-0=10
slope=10/8=5/4=1.25 (dunno if your program wants fraction or decimal)
for DEF
'run' is 19-15=4
'rise'=20-15=5
slope=5/4=1.25
they are equal because the 2 triangles are similar (congruent means exactly the same but they are different sizes)
