## Trigonometry (10th Edition)

$A=19^{o}25^{\prime}$ $B=70^{o}35^{\prime}$ $c=390.28$
$a$ is the side opposite to A, b is adjacent to it, $a=129.7, b=368.1$ $\displaystyle \tan A=\frac{a}{b}=\frac{129.7}{3681}$ $A\displaystyle \approx\tan^{-1}(\frac{129.7}{368.1})\approx$19.409904444$8^{o}\approx 19^{o}25^{\prime}$ $A+B=90^{\mathrm{o}}$ $19^{o}25^{\prime}+B=90^{\mathrm{o}}$ $B=90^{\mathrm{o}}-19^{o}25^{\prime}=70^{o}35^{\prime}$ $\displaystyle \sin A=\frac{a}{c}$ $c=\displaystyle \frac{a}{\sin A}=\frac{129.7}{\sin 19.4099}\approx$390.281650954$\approx 390.28$