The similarity of the triangles is the AA postulate
Explaining how the similarity is the AA postulate
From the question, we have the following parameters that can be used in our computation:
The triangles
In geometry, the AA postulate (or angle-angle similarity postulate) states that if two triangles have two pairs of corresponding angles congruent, then the triangles are similar.
In other words, if ∠A ≅ ∠A', ∠B ≅ ∠B', then ΔABC ~ ΔA'B'C'.
In this case, we have that
∠FHJ ≅ ∠IJG and ∠JFH ≅ ∠JGI
Hence, the similarity is the AA postulate