Respuesta :

To solve this we can apply the law of sines. WIth law of sines, we have:

[tex] \frac{\sin{A}}{a}=\frac{\sin{B}}{b}=\frac{\sin{C}}{c} [/tex]

So, we do not know B, c or C. To find either angle or side c, we hav to find angle B first and the rest will follow. To find angle B, we can do:

[tex] \frac{\sin{15}}{9}=\frac{\sin{B}}{10} \implies \\ \frac{10\sin{15}}{9}=\sin{B} \implies\\ .29=\sin{B} \implies \sin^{-1}(.288)=B \implies\\ 16.77^{\circ}=B[/tex]

So, we have [tex]A=15^{\circ}, B=16.77^{\circ} \implies\\ A+B+C=180 \implies \\ C=180-(A+B)=180-31.77=148.23 [/tex]

So, we have to solve:

[tex] \frac{\sin{16.77}}{10}=\frac{\sin{148.23}}{c} \implies \\
c=\frac{\sin(148.23)*10}{\sin{16.77}} \implies\\
c\approx 18.2480088 [/tex]