The answer should be c, no. First, the angle A is 36 and AB=AC, then the triangle ABC is an isosceles triangle, then the angle B= the angle C=? (180-36) = 72, so a is positive.

Indeed, it is proved that triangle AOD and triangle BOD are congruent, and after congruence, the angle ABD = 36, so the remaining angle ABD = 36, so it is also correct to divide B equally, and the C option is changed from D to BC.

The straight line intersects BC at point E, BD bisects the angle ABC, and the distance from the bisector of the angle to both sides of the angle is equal, so OD=DE, and the area of the triangle BCD =? BC. Delaware

The area of triangle BOD =? Bo. OD calculates the degree angle BDC=72, so the triangle DBC is also an isosceles triangle, and BC=BD.

So BC and BO are definitely not equal, and the area is definitely not equal. The d option to run the triangle similar golden section should prove that AD/AC=CD/AD. We know that AD=BD.

It has just been proved that triangle ABC is similar to triangle BCD, BC/AC=BC/AD, so triangle DBC is also an isosceles triangle BC=BD. Finally, it is proved that this ratio AD/AC=CD/AD is indeed the golden section.