Question 1194776
Description for a figure:
points D, A, R for Donald, Anton, Richard


{{{sin(34)/54=sin(D)/74}}}

{{{sin(D)=(74/54)sine(34)}}}-----for two possible angles at point D.


Also use Triangle Inequality Theorem to understand the possible range of values for length RD.   (not finished)



D may have angle measure (the interior angle) of either 50 degrees or 130 degrees.  (Pick which makes sense.


Use the Unit Circle for reference among 50 degrees and 130 degrees.


Know sum of angles measures of triangles.
One of your possibles is D 50 degree, R 34 degree, A 126 degree.
Other possible is D 130 degree, R 34 degree, A 16 degree.  


Law of Cosines, or Law Of Sines?  You choose!


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If apply Law Of Cosines, unknown segment RD,
{{{(RD)^2=54^2+74^2-2*54*74*cos(A)}}};
Try both values for A, and see what that shows.