Parallelogram is unstable and easy to deform. In real life, people often use this property of parallelogram to make school gates, lifting platforms and so on. This property can make the parallelogram achieve different effects through expansion and contraction. Parallelogram can be transformed into rectangle, square, diamond and so on.
Expand knowledge:
Moreover, parallelogram also has the following properties: diagonal bisection of parallelogram: diagonal bisection of parallelogram, that is, the intersection point of diagonal divides the diagonal into two sections, and the two sections are equal in length. Equal relative angles: The relative angles (angles between opposite sides) of a parallelogram are equal. In other words, the two angles where diagonal lines intersect are equal in size.
Parallel sides: The opposite sides of a parallelogram are parallel. That is, each pair of adjacent edges is parallel. The complementary angle sum of adjacent angles is 180 degrees: the sum of adjacent angles of parallelogram (the angle sandwiched by adjacent sides) is equal to 180 degrees. These properties are the basic characteristics of parallelogram, which can be used to judge whether a figure is a parallelogram or not, or to solve problems related to parallelogram according to these properties.
Equal side length: the opposite sides of parallelogram are equal in length. In other words, two opposite sides are equal in length. Cross-hair bisection: the cross-hair of a parallelogram is bisected, that is, the intersection of the cross-hair divides the cross-hair into two sections with equal length.
The bottom angle is equal to the top angle: a pair of adjacent angles at the bottom (two angles adjacent to the bottom) and a pair of adjacent angles at the top (two angles adjacent to the top) of the parallelogram are equal respectively.
Equal base angle: If a line segment is divided by two parallel lines, then the line segment is equal to the base angle of the triangle formed by the two parallel lines. These properties enable us to understand and apply parallelogram more deeply. They can be used to prove and solve theorems and problems related to parallelograms.