bonjour
1 ) P = 5 x + 10 + 3 x + 6 + 5 x - 10 - ( 3 x +6 ) + 7 x + 14 - ( 3 x + 6 ) + 3 x + 6 + 7 x + 14
= 13 x + 6 - 3 x - 6 + 7 x + 14 + 3 x - 3 + 4 x + 27
= 24 x + 38
2 ) aire = on divise la figure en 2
( 3 x + 6 ) ( 5 x + 10 - 3 x + 6 )
= ( 3 x + 6 ) ( 2 x + 16 )
= 6 x² + 48 x + 12 x + 96
= 6 x² + 60 x + 96
(7 x + 14 ) ( 3 x + 6 ) = 21 x² + 42 x + 42 x + 84
= 21 x² +84 x + 84
Aire = 27 x² + 104 x + 180