Question 1151182
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@greenestamps has a great solution. I don't have much to add other than a diagram that might help supplement his work.


<img src = "https://i.imgur.com/bviLAKU.png">


Edit: @ikleyn makes a great point that it is not clearly stated anywhere that ABC is 90 degrees. Hopefully that information is posted elsewhere in your textbook (perhaps in a previous problem). The visual cue that ABC could be 90 degrees came from the fact that ABC looks like a square angle. If ABC is not 90 degrees, then the whole thing falls apart.
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