Answer:
170
Step-by-step explanation:
A heptagon's internal angles add up to 900 degrees.
So:
(2x-13)+(3x-8)+(2x-3)+(2x-7)+(3x-1)+(2x+11)+(2x+9) = 900
16x - 12 = 900
16x = 912
x = 912/16
x = 57
3x - 1 = 3 * 57 -1 = 170
