Answer:
The correct option is;
∠A ≅ ∠A ; reflective property
Explanation:
1. ΔABC is isosceles with legs AB and AC
ΔAYX is also isosceles with legs AY and AX
2. AB ≅ AC and AY ≅ AX (Definition of isosceles triangle)
3. AB = AC and AY = AX (Definition of congruency)
4. AY · AC = AX · AC (Multiplication property of equality)
5. AY · AC = AX · AB (Substitution property of equality)
6.
(Division property of equality)
7.
(Division property of equality)
8. ∠A ≅ ∠A ; reflective property
9. ΔABC ~ ΔAXY SAS similarity theorem (The two triangles have the same vertex angle A hence they are similar based on the Side Angle Side theorem for uniqueness of triangles.