# How do you find the exact value of the third side given triangle RST, RS=0.375, ST=1.29, mangleS=167?

Feb 25, 2018

Length of third side $\textcolor{b r o w n}{s = 1.65753673796}$

#### Explanation:

$t = 0.375 , r = 1.29 , \hat{S} = {167}^{\circ}$

To find length of side $s$

$s = \sqrt{{r}^{2} + {t}^{2} - \left(2 r t \cos S\right)}$

$\implies \sqrt{{1.29}^{2} + {0.375}^{2} - \left(2 \cdot 1.29 \cdot 0.375 \cos \left(167\right)\right)}$

$\textcolor{b r o w n}{s = 1.65753673796}$