Answer:
1080
Explanation:
lets take any shape with n sides
now lets take a point in inside the shape and draw triangles with each side serving as one base of the triangle
now we will have n triangles
sum of angles of all triangls = n * 180
if we subtract the central angle, we will have the sum of interior angles
the central ange is 360 ,so the sum of internal angles = n *180 -360
simplifying n * 180 -360 = 180(n-2)