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MathNet 2017-part-07 — 172 problems (EN–VI) Question 73

Math Olympiad Vault · MathNet 2017-part-07 — 172 problems (EN–VI)

Question 73

The area of square $ABCD$ is $196~\mathrm{cm}^2$. Point $E$ is inside the square, at the same distances from points $D$ and $C$, and such that $\angle DEC = 150^\circ$. What is the perimeter of $\triangle ABE$ equal to? Prove your answer is correct.