∴∠ 1=∠2(∠abd=∠2,∠bad=∠ 1)
AB = AC = CD
∴∠2=∠3(∠3=∠ACB)
∴∠4=∠5
Mark ∠4 as ∠DAC.
∵∠2+∠3+(∠ 1+∠4)= 180
And ≈5(≈ADC) is the exterior angle of △ABD =∠2+∠3.
∴∠ 2+∠ 3+∠ 1+∠ 2 = 180 (because all three angles are equal).
∴∠ 1=36
∴∠5=36+36=72
∴∠4=72
∴∠BAC=∠4+∠ 1= 108