Answer:
14
Step-by-step explanation:
Number of sides (n) = 10
Sum of all angles of polygon = (n - 2 )* 180
= 8 * 180 = 1440
As this is a regular polygon,
measurement of each angle = 1440/10 = 144
10x + 4 = 144
10x = 144- 4
10x = 140
x = 140/10
x = 14
