Solution
For this case we need to take in count that:
[tex]\pi=180[/tex]
Then we can do this:
[tex]\frac{\pi}{5}=36\text{degrees}[/tex]
And we can convert -155° on this way:
[tex]\frac{x}{-155}=\frac{\pi}{180}[/tex]
Solving for x we got:
[tex]x=-155\cdot\frac{\pi}{180}=-\frac{31}{36}\pi[/tex]
