bonjour
figure 1
P = 2 ( 8 + 7 x + 5 ) = 16 + 14 x + 10 = 14 x + 26
figure 2
rectangle du haut
Longueur = 3 x + 6
Largeur = 5 x + 10 - ( 3 x + 6 ) = 5 x + 10 - 3 x - 6 = 2 x + 4
Aire = ( 3 x + 6 ) ( 2 x + 4 ) = 6 x² + 12 x + 12 x + 24 = 6 x² + 24 x + 24
rectangle du bas
( 3 x + 6 ) ( 7 x + 14 ) = 21 x² + 42 x + 42 x + 84 = 21 x² + 84 x + 84
aire totale = 6 x ² + 24 x + 24 + 21 x² + 84 x + 84
= 27 x² + 108 x + 108
