Answer:
A = 58.5°
Set your calculator to degree mode.
sin(31.5°) = 15.3/c
c sin(31.5°) = 15.3
c = 15.3/sin(31.5°) = 29.3
tan(31.5°) = 15.3/a
a tan(31.5) = 15.3
a = 15.3/tan(31.5°) = 25.0
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