Svp ! j'y arrive pas
Question
1 Réponse
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1. Réponse taalbabachir
Réponse :
compléter le tableau suivant
AB = 4 cm AD = 12 cm AE = 5 cm
A'B' = 2 cm A'D' = 6 cm A'E' = 2.5 cm
Aabcd = 48 cm² Afgcb = 60 cm² Aghdc = 20 cm²
Aa'b'c'd' = 12 cm² Af'g'c'b' = 15 cm² Ag'h'd'c' = 5 cm²
Vabcdefgh = 240 cm³
Va'b'c'd'e'f'g'h' = 30 cm³
Explications étape par étape
A'B' = 1/2) x AB = 1/2) x 4 = 2 cm
A'D' = 1/2) x AD = 1/2) x 12 = 6 cm
A'E' = 1/2) x AE = 1/2) x 5 = 2.5 cm
Aabcd = AD x AB = 4 x 12 = 48 cm² ⇒ Aa'b'c'd' = (1/2)² x 48 = 48/4 = 12 cm²
Afgcb = FG x FB = AD x AE = 12 x 5 = 60 cm² ⇒ Af'g'c'b' = 60/4 = 15 cm²
Aghdc = CD x HD = AB x AE = 4 x 5 = 20 cm² ⇒ Ag'h'd'c' = 20/4 = 5 cm²
Vabcdefgh = AB x AD x AE = 4 x 12 x 5 = 240 cm³
Va'b'c'd'e'f'g'h' = (1/2)³ x 240 = 240/8 = 30 cm³