Question

1) if the sum of interior angles of a polygon is 1260, then find the no of sides of it

2) therefore find x (in the picture)

Answer 1

1- s=(n-1)×180

1260=(n-1)×180

1260/180=n-1

70=n-1

71=n

2-at angle 120 there is a linear pair angle.

y+120=180°

y=60°

x+60+110+60=360°

x=360°-230°

x=130°