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Meilleure réponse !
2014-02-10T14:34:23+01:00
Bonjour
AE = FB = DH = CG = x+2 
AD = BC = FG = EH = x+3
AB = CD = EF = GH = 9  
Longueur totale des arêtes = 4(x+2)+4(x+3)+4(9) = 8x + 56 

Aire ABCD = Aire EFGH = 9(x+3)
Aire AEHD = Aire BFGC = (x+2)(x+3) 
Aire AEFB = Aire HGCD = 9(x+2) 
Aire totale = 2(9(x+3)) + 2(x+2)(x+3) + 2(9(x+2)) = 2x²+46x+102 

Volume total = 9(x+2)(x+3) = 9(x²+5x+6) = 9x²+45x+54