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# Triangles: Isosceles

Correct. [[snippet]] Since angle $$AED$$ and angle $$DEC$$ are supplementary angles, >$$\angle AED = 180^\circ - 160^\circ = 20^\circ$$. Given that $$EAD$$ is an isosceles triangle, you can find the measure of the base angles: >$$\angle EAD = \frac{180^\circ - 20^\circ}{2} = 80^\circ$$.