UKMT Pink Kangaroo, 2020

Geometry Difficulty 2.0 Junior Find the answer United Kingdom

A vertical stained glass square window of area $81 \text{ cm}^2$ is made out of six triangles of equal area (see figure). A fly is sitting on the exact spot where the six triangles meet. How far from the bottom of the window is the fly sitting?

(A) $3$ cm (B) $5$ cm (C) $5.5$ cm (D) $6$ cm (E) $7.5$ cm

Figure for this problem

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