Using the Sine Rule,
\(\frac{16}{sin(54)}=\frac{12}{sin C}\)
\(12sin(54)=16sinC\)
\(sinC=\frac{3sin54}{4}\)
\(C = sin{}^{-1}(\frac{3sin54}{4})\)which is about 37.35579 degrees
54 + 37.35579...... + A = 180 (angle sum of triangle)
A = 88.6442......
Applying the Sine Rule again,
\(\frac{a}{sin A}=\frac{16}{sin54}\)
\(a = \frac{16sin88.6442......}{sin54}=19.77155\)
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