There is a formula to determine the size of each interior angle of the polygon with sides n.
[tex]Angle = (n-2)( \frac{180}{n} )[/tex]
A decagon is a polygon with 10 sides. So, we substitute n with 10.
[tex]Angle = (10-2)( \frac{180}{10} )[/tex]
Angle = 144 degrees
Thus, the each angle of the sign's side is 144 degrees.
I hope I was able to explain it clearly. Have a good day.
