Answer:
each polygon has as many sides as angles
n= number of angles and therefore number of sides
....the interior angle of a polygon = 180n-360
6)180n-360=1080
180n=1080+360
180n=1440
n= 1440/180=8
octagon
7) 180n-360=1440
180n = 1440+360
180n=1800
n=10
decagon
8) 180n-360=2340
180n=2340+360
180n=2700
n=15
pentadecagon
9)180n-360=180
180n=180+360
180n=540
n=3
triangle
10) 180n-360=3600
180n=3600+360
180n=3960
n=22
doicosagon
11)180n-360=540
180n =540+360
180n=900
n=5
Pentagon
Explanation: