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SAI International School
                                                      CLASS-VII

               Mathematics
               CHAPTER-11: Area and Perimeter
               LESSON NOTES-2



               SUBTOPIC: Area of Parallelogram


               LESSON NOTES:

               Area of Parallelogram:A parallelogram is a 4-sided shape formed by two pairs of
               parallel lines.

                     Opposite sides are equal in length and opposite angles are equal in measure
                       as shown in the figure.






















                     Area of the parallelogram = area of the rectangle formed
                     We find that the length of the rectangle formed is equal to the base of the
                       parallelogram and the breadth of the rectangle is equal to the height of the
                       parallelogram as given in the above figure.
                     Now, Area of parallelogram = Area of rectangle
                                                                     = length × breadth = l × b

                     But the length l and breadth b of the rectangle are exactly the base b and the
                       height h, respectively of the parallelogram.
                     Thus, the area of parallelogram = base × height = b × h.
                     Any side of a parallelogram can be chosen as base of the parallelogram. The
                       perpendicular dropped on that side from the opposite vertex is known as
                       height (altitude).
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