Answer
$c \approx13.16$
$A \approx31.6^\circ$
$B \approx 48.4^\circ$
Work Step by Step
1. Use the Law of Cosines, we have $c=\sqrt {7^2+10^2-2(7)(10)cos100^\circ}\approx13.16$
2. Use the Law of Sines, we have $\frac{7}{sinA}=\frac{13.16}{sin100^\circ}$ and $A=sin^{-1}(\frac{7sin100^\circ}{13.16})\approx31.6^\circ$
3. Thus $B=180-A-C\approx180-100-31.6=48.4^\circ$
