Question

what is the sum of the measure of the angles of a convex quadrilateral ? will the property hold if the quadrilateral is not convex

Answer 1

yes and sum of angle is 360

Answer 2

Answer:

ABCD is convex quadrilateral made of 2 triangles △ABD and △BCD.

The property will held because the quadrilaterals are made of two triangles and sum of angles of interior angles of quadrilateral = Sum of interior angles of two triangles.

Here, ABCD is concave.

Sum of interior angles of quadrilateral ⇒ 180 + 180

= 360