Am i doing this right? 16,14=4 15,35=5 24,32=4 27,63=9 20,80=20 18,38=2 14,49=7 66,99=33 9,35=1 6,24,42=6 30,50,70=10 32,48,96=12 10w,5w=5 16xy,24xy=8 21ab,35a=7 10jk,15k=5 3mn,9mn,12mn=3 6xy,9x,3y=3

GCF(16, 14) = 2   Note: 14 is not divisible by 4.
GCF(24, 32) = 8 because
  24 = 2 x 2 x 2 x 3
  32 = 2 x 2 x 2 x 2 x 2   GCF = 2 x 2 x 2 = 8
GCF(10w, 5w) = 5w  because the w is a common factor, too.
GCF(16xy, 24xy) = 8xy  because x and y are factors common to both
GCF(21ab, 35a) = 7a because a is a common factor, but b is not
GCF(10jk, 15k) = 5k
GCF(3mn, 9mn, 12mn) = 3mn

Yes i could be the length of the triangle