The area of the quadrilateral.
Area
It depends on what kind of quadrilateral is. Still, you can't solve it.
square, rhombus
parralelogram
The area of the quadrilateral.
A Quadrilateral has two diagonals. IF the quadrilateral is a rectangle, then the two diagonals are equal in length.
Nope - a quadrilateral is defined as having four sides of equal length.
Yes, be it a common convex quadrilateral or a concave quadrilateral. For a convex quadrilateral, the most obvious example is a irregular trapezium, where the upper base and the lower base are of different length, and the slanted sides are of different length. It is similar for a concave quadrilateral.
One.
Area
rhombus
Area divided by length= width
No, a quadrilateral must have 4 sides. If it is a proper quadrilateral it must have 4 sides of equal length but if it is an irregular quadrilateral it must have 4 sides but not have equal sides. An example of a quadrilateral could be a square. A pentagon on the other side must have 5 sides.
trapezium
It depends on what kind of quadrilateral is. Still, you can't solve it.
No.No.No.No.