Rectangle:                                         .

• Properties of a rectangle:

  The diagonals are                          . Opposite sides are                   .        

Square:                                        .

Property 1: The rectangle is divided into four rectangles with areas as shown. Describe the relationship of x, y, u, v: 

How to proof?

Property 2: P is any point inside rectangle ABCD, Describe the relationship of AP, PC, BP, PD. 

How to proof?

Property 3: In rectangle ABCD, E and F are any two points on BC and CD, respectively. Find the relationship.

How to proof?

Property 4: P is any point inside rectangle ABCD, Describe the relation of area of 4 parts.

How to proof?