Answer:
the number of sides is 12
Explanation:
The computation of the number of sides in the polygon is shown below:
As we know that
S_n = n ÷ 2 (a_1 + a_n)
= n ÷ 2 × (128 + 172)
= 150 n
Now given that the sum of the measures = 180 (n - 2)
So,
Sn = 180 (n - 2)
150n = 180n - 360
30n = 360
n = 12
Hence, the number of sides is 12