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UKMT Intermediate Mathematical Challenge, 2026

Geometry Difficulty 2.0 Junior Find the answer United Kingdom

A triangle has sides in the ratio $5:5:6$ and area $108\text{ cm}^2$ . What is the length, in cm, of the longest side of the triangle?

(A) $15$ (B) $18$ (C) $21$ (D) $24$ (E) $27$

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