Showing posts with label quadrilateral. Show all posts
Showing posts with label quadrilateral. Show all posts

Friday, August 10, 2012

Introduction for angle sum property of quadrilateral


Introduction for angle sum property of quadrilateral:

              A quadrilateral is a two-dimensional figure created by connecting four segments endpoint to endpoint with each segment intersecting exactly two others. It also has four sides and four angles. Sum of interior angle of any polygon is (n-2) 180o. Here quadrilateral has four sides so interior angle is (4-2)180o = 360o.Exterior angle of any polygon is 360o so the exterior angle of a quadrilateral is 360o.

Types of Quadrilaterals
  • Trapezoid
  • Parallelogram
  • Square
  • Rectangle
  • Rhombus 
 
Angle Sum Property of Quadrilateral- Trapezoid
  • The sum of the adjacent angles are equal to 180o
  • The sum of all the interior angles are equal to 360

  • In the above figure  the sum of two adjacent angles are equal to 180o
          100 + 80 = 180
          100 + 80 = 180
  • The sum of all the internal angles are equal to 360o
           100 + 100 + 80 + 80 = 360
        

Angle sum property of Parallelogram:
  • The opposite angles of a parallelogram are equal
  • The opposite sides of a parallelogram are parallel
 
  • In the above diagram The sum of all the interior angles are equal to 360o
               110 + 70 + 110 + 70 = 360
  • The sum of the adjacent angles are equal to 180o
                 110 + 70 = 180
              110 + 70 = 180

Angle sum property of Square
  • All the four sides of a square are equal
  • All the four angles of a square are equal, And the angles are equal to 90o
  • The sum of all the internal angles are equal to 360o
     

  • In the above diagram, All the four angles of a square are equal, And the angles are equal to 90o
                      90 + 90 + 90 + 90 = 36o
Angle Sum Property of Quadrilateral- Rectangle
  • All the four angles of a square are equal, And the angles are equal to 90o
  • The sum of all the internal angles are equal to 360o
    
  • In the above diagram, The sum of all the internal angles are equal to 360o
                 90 + 90 + 90 + 90 = 360o


Angle sum property of Rhombus
  • The sum of all the internal angles are equal to 360o
  • Opposite angles of a rhombus are equal 
  • In the above diagram, The sum of all the internal angles are equal to 360o
                       115 + 65 + 115 + 65 = 360