x = 144 degrees
We know there are 10 sides on this polygon, and we know the sum of interior angles in a regular polygon is represented as 180*(s-2) where s is the number of sides.
With this, we know that the sum of interior angles on a 10-sided regular polygon is 180*(10-2)=1440.
We also know that the measure of angle x = the measure of any other interior angle in the 10-sided polygon.
Using substitution, we know that 10x = 1440 degrees so x = 144 degrees.
