(*) Ptolemy's inequality gives a relationship between the sides and diagonals of one of these shapes, and Brahmagupta's Formula can also be used to find the area of one of these polygons that is inscribed in a circle, those are known as the "cyclic" types of these shapes.
Bretschneider's Formula gives the area of one of these figures, and Varignon's Theorem describes the shape formed when connecting the midpoints of one of these shapes. One of these shapes is describable with 5 parameters, while the midpoints of the diagonals of a "complete" one of these shapes are collinear. (*) Ptolemy's inequality gives a relationship between the sides and diagonals of one of these shapes, and Brahmagupta's Formula can also be used to find the area of one of these polygons that is inscribed in a circle, those are known as the "cyclic" types of these shapes. For ten points, name these shapes such as kites, squares, and rectangles, which have 4 sides.
Bretschneider's Formula gives the area of one of these figures, and Varignon's Theorem describes the shape formed when connecting the midpoints of one of these shapes.
quadrilateral [accept anything more specific, such as cyclic quadrilateral] &lt;MS&gt;