Let's take a look at the situation:
Using the law of sines
[tex]\frac{5280}{\sin90}=\frac{450}{\sin\theta}[/tex]Solving for theta,
[tex]\begin{gathered} \frac{5280}{\sin90}=\frac{450}{\sin\theta} \\ \\ \rightarrow\frac{5280\sin\theta}{\sin90}=450\rightarrow5280\sin \theta=450\rightarrow\sin \theta=\frac{450}{5280} \\ \\ \theta=\sin ^{-1}(\frac{450}{5280})\Rightarrow\theta=4.88 \end{gathered}[/tex]This way, the inclination of the road, round to the nearest degree is 5°
