Answer: x = 9
Step-by-step explanation:
x + 20 = 29
x = 9
9 + 20 = 29
Diagonals are = n - 2
Interior = 144
Exterior angle = 180 - 144 = 36
Formula for exterior of a regular polygon given the number of sides:
= 360/n
36 = 360/n
n = 360/36 = 10
n = 10
Number of diagonals = n - 2 = 10 - 2 = 8
8 diagonals.
