(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

As given in the title. The law of cosines, the law of sines, or any other aspect of trigonometry may be used. Ultimately, I need to show that when two triangles have two pairs of proportional sides and the included angles congruent, that they are similar - that is, the remaining pair of sides are proportional and the other two angles are congruent. I could do it all if I could just prove that one of the other pairs of angles were congruent.

2. Relevant equations

3. The attempt at a solution

I've spent 3+ hours now messing around with the law of sines, the law of cosines, and anything else I could think of. I honestly have no idea; nothing I've tried seems remotely close.

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# Homework Help: Prove the SAS Triangle Similarity Theorem from Trigonometry

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