angles EFH and GFH are congruents
for the second equivalence criterion two triangles are equivalents if they have respectively 2 angles and 1 side congruents
the two triangles have congruents the angle right angle (HGF and HEF) and the 55 degrees angles (EFH and GFH); then they have in common the HF side.
so the triangles are congruent and so all the sides are respectively congruent,for example EH with HG:
EH=HG
s+36=7s
s+36-7s=0
s-7s=-36
-6s=-36
6s=36
s=6
sorry for my english