It is known that ab = AC, BD = DC, AE bisects ∠ fac, Q: is AE perpendicular to ad? Why?

It is known that ab = AC, BD = DC, AE bisects ∠ fac, Q: is AE perpendicular to ad? Why?

It is proved that: ∵ AB = AC, CD = BD, ∵ 1 = ∵ 2, ∵ B = ∵ C, ad ⊥ BC, and ∵ AE is the bisector of △ ABC, ∵ 3 = ∵ 4 = 12 (∵ B + ∵ C) = ∵ C, ∵ AE ∥ BC, ∵ Dae + ∵ ADB = 180 ° and ∵ ad ⊥ BC, ∵ DAE = ∵ ADC = 90 °. AE ⊥ ad