# Relation for hyperbolic pentagon.

I am trying to get a relation between the length of the sides and the angles of a hyperbolic pentagon. In literature I can find relations for pentagons which has at least three Right angle. So my question is the following.

Let S be a hyperbolic pentagon with angles $\alpha_1,...,\alpha_5$ and with sides $l_1,...,l_5$ such that $\alpha_i\neq\pi/2$ for all $i$. Is there any formula relating $\alpha_i$ with $l_i$.

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