# Trigonometry! #124

Geometry Level 3

In $$\Delta ABC$$, $$s$$ represents the semiperimeter and $$r_{1}$$ represents the radius of the excircle opposite to $$A$$. If $$3s^{2}=r_{1}^{2}$$, then enter the degree measure of $$\angle A$$.

This problem is part of the set Trigonometry.

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