Answer:
AB ≅ AC since triangle ABC is an isosceles triangle.
Step-by-step explanation:
- If angle 1 and angle 2 are equal, then triangle ADE is an isosceles triangle.
- Since line DE is parallel to line BC, then angle 2 is equal to angle 3 and angle 1 is equal to angle 4 (corresponding angles are equal).
- Since angle 3 is equal to angle 2 and angle 4 is equal to angle 1, then angle 3 is equal to angle 4.
- Since angle 3 is equal to angle 4, then triangle ABC is an isosceles triangle that have equal base angles (i.e angle 3 and angle 4).
- The two sides of the isosceles triangle ABC (i.e sides AB and AC) are also equal.
- Hence AB ≅ AC
