Answer:
Approximatley 5.8 units.
Step-by-step explanation:
We are given two angles, ∠S and ∠T, and the side opposite to ∠T. We need to find the unknown side opposite to ∠S. Therefore, we can use the Law of Sines. The Law of Sines states that:
![\frac{\sin(A)}{a}=\frac{\sin(B)}{b} =\frac{\sin(C)}{c}](https://tex.z-dn.net/?f=%5Cfrac%7B%5Csin%28A%29%7D%7Ba%7D%3D%5Cfrac%7B%5Csin%28B%29%7D%7Bb%7D%20%3D%5Cfrac%7B%5Csin%28C%29%7D%7Bc%7D)
Replacing them with the respective variables, we have:
![\frac{\sin(S)}{s} =\frac{\sin(T)}{t} =\frac{\sin(R)}{r}](https://tex.z-dn.net/?f=%5Cfrac%7B%5Csin%28S%29%7D%7Bs%7D%20%3D%5Cfrac%7B%5Csin%28T%29%7D%7Bt%7D%20%3D%5Cfrac%7B%5Csin%28R%29%7D%7Br%7D)
Plug in what we know. 20° for ∠S, 17° for ∠T, and 5 for <em>t</em>. Ignore the third term:
![\frac{\sin(20)}{s}=\frac{\\sin(17)}{5}](https://tex.z-dn.net/?f=%5Cfrac%7B%5Csin%2820%29%7D%7Bs%7D%3D%5Cfrac%7B%5C%5Csin%2817%29%7D%7B5%7D)
Solve for <em>s</em>, the unknown side. Cross multiply:
![\frac{\sin(20)}{s}=\frac{\sin(17)}{5}\\5\sin(20)=s\sin(17)\\s=\frac{5\sin(20)}{\sin(17)} \\s\approx5.8491\approx5.8](https://tex.z-dn.net/?f=%5Cfrac%7B%5Csin%2820%29%7D%7Bs%7D%3D%5Cfrac%7B%5Csin%2817%29%7D%7B5%7D%5C%5C5%5Csin%2820%29%3Ds%5Csin%2817%29%5C%5Cs%3D%5Cfrac%7B5%5Csin%2820%29%7D%7B%5Csin%2817%29%7D%20%5C%5Cs%5Capprox5.8491%5Capprox5.8)