The interior angles of a polygon form an arithmetic sequence. The difference between the largest angle and smallest angle is $56^\circ$. If the polygon has $3$ sides, then find the smallest angle, in degrees.
Call the smallest angle x and the common difference d
x + (x + d) + (x + 2d) = 180
3x + 3d = 180
x + d = 60
(x + 2d) - x = 56
2d = 56
d = 56 / 2 = 28
x + 28 = 60
x = 60 - 28 = 32° = the smallest angle
+470 
