Geometry

In \triangle PQR, we have \angle P = 90^\circ, PQ=3, and QR = 5. Find \tan R.   

By Pythagoras  PR² = QR² – PQ²    

                          PR  =  sqrt(25 – 9)  =  4     

                       tan R  =  opposite over adjacent  =  3 / 4      

                       tan R  =  0.7500    

If you draw / label the triangle, the answer becomes clear.    

I'd like to show you, but I don't know how to post a picture.   

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