What Is a Quadrangle?
A closed plane figure or three-dimensional figure which is surrounded by four non-intersecting line segments that are not on the same straight line in turn is called a quadrilateral, and is composed of a convex quadrilateral and a concave quadrilateral. A quadrilateral obtained by sequentially connecting the midpoints on any quadrilateral is called a midpoint quadrilateral, and the midpoint quadrilaterals are all parallelograms. The midpoint quadrilateral of the rhombus is rectangular, the midpoint quadrilateral of the rectangle is rhombus, the midpoint quadrilateral of the isosceles trapezoid is rhombus, and the midpoint quadrilateral of the square is square.
Quadrilateral definition
- A line segment connecting any two non-adjacent vertices of a quad (a quad has two diagonal lines). [2]
Quadrilateral
- The quadrangular area is equal to half the product of the two diagonals. [2]
- Example: In quadrilateral ABCD, ACBD, then S ABCD = 1/2 · AC · BD
Quadrilateral special
- Special quadrilaterals with vertical diagonals are: diamond, square, special trapezoid. [2]