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masters Use law of sines to find angle B. See diagram.
$\displaystyle \frac{\sin 15}{8}=\frac{\sin B}{11}$
$\displaystyle \sin B=\frac{11 \sin 15}{8} \approx .3559$
$\displaystyle \sin^{-1}=20.8^{\circ}$
$\displaystyle \angle C=144.2^{\circ}$
Now, use the law of sin again to find the missing side c.
$\displaystyle \frac{\sin 15}{8}=\frac{\sin 144.2}{c}$
Once you find c using the formula above, you will have all the sides needed.
P = a + b + c
Use Heron's formula to find the area:
$\displaystyle A=\sqrt{s(s-a)(s-b)(s-c)}$ where $\displaystyle s=\frac{a+b+c}{2}$