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Area of special quadrilaterals:
                  To find the area of rhombus, we can split it into two triangles by drawing one of its
                  diagonals as shown in the given figure.

                  Area of rhombus ABCD = (area of ΔACD) + (area of ΔABC)
                                            = (1/2) * AC * OD + (1/2) * AC * OB
                                            = (1/2) * AC * (OD + OB)
                                            = (1/2) * AC * BD
                                           = 1/2 * d1 * d2
                  where AC = d1 and BD = d2


                  Example : The diagonals of a rhombus are 7.5 cm and 16 cm. Find its area.
                  Solution: Given: d1 =7.5 cm and d2 = 16 cm


                  Area of rhombus = 1/2 * d1 * d2
                                      = 1/2 * 7.5 * 16
                                      = 7.5 * 8
                                      = 60 cm  2
                  Hence, area of rhombus is 60 cm .
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                  Area of Polygon
                  We split a polygon into triangles and then find its area.

                  Ex: To find the area of given figure, by constructing two diagonals AC and AD the
                  pentagon ABCDE is divided into three parts.

                  So, area ABCDE = area of Δ ABC + area of Δ ACD + area of Δ AED.































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