difference between convex and concave polygons

how can we judge convex and concave polygon

there are many ways to judge convex and concave polygon .

first way:

convex polygon : if all the diagonals of a polygon lie inside it , it is called convex polygon

concave polygon : if any one of the diagonals lie outside the polygon , it is called concave polygon

another way:

convex polygon : if all the interior angles of a polygon are less than or equal to 180, it is called convex polygon

concave polygon: if one or more than one interior angle of a polygon is greater than 180, it is called concave polygon