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CBSE Class 9 Answered

herons formula
Asked by yashpinto | 08 Dec, 2009, 02:52: PM
answered-by-expert Expert Answer

Length + Breadth + Height , (l + b + h) = 19 cm

Diagonal =   (l2 + b2 + h2) = 11 cm

Surface Area of cuboid = 2 (lb + bh + hl)

                                          = ( l + b + h)2 - (  (l2 + b2 + h2))2

                                         = Square of Sum of dimensions - square of diagonal

[ Since, ( l + b + h)2 = l2 + b2 + h2 + 2lb + 2bh + 2hl]

 

Answered by | 08 Dec, 2009, 03:15: PM

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