



 
Darya, Use the formula $S = \frac12 b c \sin A,$ where $S$ is the area, to find the angle A between edges b and c. Then use the cosine law $a^2 = b^2 + c^2  2 b c \cos A$ to find a. Heron's formula (look it up!) leads to a solution too. While it involves solving a fourth degree equation for a, it is actually a quadratic in $a^2$ so can be solved fairly easily. Good Hunting!  


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