Answer:
1,2,3 and 6 are similar triangles by AA similarity
Step-by-step explanation:
1) ∠DEC ≅ ∠FEG {Vertically opposite angles}
DC // GF
∠ECD ≅ ∠EGF {Alternate interior angles}
∠EDC ≅ ∠EFG {Alternate interior angles}
ΔDEC & ΔFEG are similar triangles by AA similarity
2)MN // QP
∠LQP ≅ ∠QMN {Corresponding angles }
∠LPQ ≅ ∠PNM {Corresponding angles}
ΔLQP & ΔLMN are similar triangles by AA similarity
3) In ΔSYE ,
∠S = 180 - 90 - 39
∠S = 51°
In ΔCHW,
∠H = 180 - 51 - 90
∠H = 39
ΔSYE and ΔCHW
∠S ≅ ∠W = 51°
∠Y ≅ ∠C = 90°
∠E ≅∠H = 39°
ΔSYE & ΔWCH are similar triangles by AA similarity
6) ∠P ≅ ∠Z {Given}
∠PXQ ≅∠ZXY {Vertically opposite angles}
ΔPXQ & ΔZXY are similar triangles by AA similarity