I really don't understand this. Can someone help me.
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Answer:
Step-by-step explanation:
sum of angles of a polygon=(n-2)*180
S=(n-2)*180
n=13
S=(13-2)*180
=11*180
=1980°
2.
sum of angles=95+140+120+75+130+115+80
=750
again sum of angles of a heptagon=(7-2)×180
=5×180
=900
so these can,t be angles of heptagon.
3.
external angle of heptagon=360÷10=36
internal angle=180-36=144°
it is a convex polygon.
4.
external angle=360÷9=40°
internal angle=180-40=140°
it is a convex polygon.
5.
external angle=360÷5=72°
internal angle=180-72=108°
it is a convex polygon.