GRE geometry questions about finding the angle between a side of a triangle and a circumradius

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I am struggling with reconciling the fact that all the middle lines are the same length with the fact that the angles aren't the same. enter image description here enter image description here

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Just try to draw the figure. Each of the triangles with peak at $D$ is isosceles, so the base angles are equal. That gives $\angle DBC=20^\circ$ so $\angle CDB=140^\circ$. $ADC$ is equilateral so $\angle CDA=60^\circ$. That leaves $\angle ADB=160^\circ$ Now just draw a circle, put a protractor at the middle, and draw the radii from the center at those angles. You will have the desired triangle.