bonjour
figure 1
P = 3 + 10 + 7 + 5 + 4 = 19
Périmètre = 29 cm
la figure se découpe en deux rectangles
3 x 10 = 30
4 x 5 = 20
Aire = 50 cm²
figure 2
P = 6 + 8 + 10 + 6 = 30 mm
6 x 2 = 12
6 x 10 = 60
Aire = 72 mm²
figure 3
P = 5 + 6 + 8 + 3 + 6 +3 = 31 m
6 x 5 = 30
3 x 13 = 39
Aire = 69 m²
figure 4
P = 6 + 4 + 5 + 8 + 9 = 32 cm
5 x 8 = 40
6 x 4 = 24
Aire = 64 cm²
