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                                                                                                2
                Example 12: In the adjoining figure, area of the parallelogram is 24 cm , and the base of the
                parallelogram is 3 cm. Find the height of the parallelogram.

                Solution: In the adjoining figure,
                                                                                                             h
                let the height of the parallelogram be h.                                                              3 cm

                Base of the parallelogram, b = 3 cm,
                We have, area of parallelogram =  b × h

                                                                                                                       2
                                                           2
                Therefore,               3 cm × h = 24 cm                 (Given, area of the parallelogram = 24 cm )
                                                     24
                \                                h =     cm = 8 cm
                                                      3
                Thus, the height of the parallelogram corresponding to base is 8 cm.

                Example 13: A side of a parallelogram measuring 12 cm is at a perpendicular distance of 15 cm
                from its opposite side. Find the area of the parallelogram.
                                                                                                          D            C
                Solution:  Base of the parallelogram, b =  12 cm,

                        Height of the parallelogram, h =  15 cm
                                                                                                           15 cm
                     We have, area of the parallelogram =  base × height

                                                         =  (12 × 15) cm 2                            A    12 cm   B
                                                         =  180 cm  2

                                                              2
                So, the area of the parallelogram is 180 cm .
                                                                                              2
                Example 14: Find the height ‘h’ if the area of the parallelogram is 48 cm  and
                the base is 4 cm.

                Solution:  Let height of the parallelogram be h cm, and                                           h

                base of the parallelogram, b = 4 cm.
                We have, area of the parallelogram =  base × height                                           4 cm

                                                     2
                                                                                                                2
                                               48 cm  =  4 cm × h         [Area of the parallelogram = 48 cm , given]
                                                     h =   48  cm = 12 cm
                                                          4
                Thus, the height of the parallelogram is 12 cm.

                Example 15: The two sides of the given parallelogram are 8 cm and 6 cm. The height corresponding
                to the base CD is 3 cm. Find the (a) area of the parallelogram. (b) the height corresponding to the
                base AD.                                                                                         B
                                                                                    A
                Solution: In the given figure,

                           (a)  Base of the parallelogram,     b = 8 cm                             h      3 cm
                                                                                         6 cm
                                Height of the parallelogram,  h = 3 cm

                                We have,  Area of parallelogram = b × h
                                                                                             D              8 cm       C
                                                                   = 8 cm × 3 cm = 24 cm  2

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