Thanks for the answer, it helped me a lot!
5sqrt(21)/41 wasn't correct, but your response helped me figure out what to do next.
I followed your solution and got mostly the same results except that I got 40/41 as cos(PAQ) instead of 34/41.
I plugged that into the relationship between the sine and cosine of PAQ and got 9/41 as the final answer, which turned out to be correct.
\( sin(PAQ) = \boxed{9/41}\)
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