Question

The octagon in the figure is equiangular and AB=AC Find m∠ACB .

Answer 1

∠ACB = ∠ABC = 360°/8 = 45°

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∠ABC is an external angle of the octagon. Since it is equiangular, all external angles are equal. The sum of external angles of a convex polygon is always 360°, so one of 8 of those angles will be 360°/8 = 45°.