I think its not a correct solution of given equations.
To Prove: ΔEFI ~ Δ GFH
Proof:
When two triangles are similar, their corresponding sides are Proportional and their corresponding interior angles are equal.
Two Triangles can be proven similar by following Similarity Criterion.
1. AA
2.SSS
3.SAS
→∠EFI=∠GFH-------[Vertically Opposite angles]
The Other statement which is needed to prove that triangles EFI and GFH are similar is
Option C:→ ∠E ≅ ∠G
So, Two triangles ΔEFI and Δ GFH are Similar by Angle-Angle(AA) Criterion.
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
11 and -28
11x-28=-308
11+-28=-17