The sum of the measures of the angles of a convex quadrilateral is 3600 as a convex quadrilateral is made of two triangles.
Here, ABCD is a convex quadrilateral, made Of two triangles \\(\ riangle A B D\\) and \\(\ riangle B C D\\).Therefore, the sum of all the interior angles of this quadrilateral will be same as the sum of all the interior angles of these two triangles i.e., \\(180^{\\circ}+180^{\\circ}=360^{\\circ}\\)
Yes, this property also holds true for a quadrilateral which is not convex. This is
because any quadrilateral can be divided into two triangles.
Here again, ABCD is a concave quadrilateral, made of two triangles \\(\ riangle A B D\\) and \\(\ riangle B C D\\) .
Therefore, sum of all the interior angles of this quadrilateral will also be \\(180^{\\circ}+180^{\\circ}=360^{\\circ}\\).