A)
P = 1/2 • 12cm • (3cm + 28cm) = 186cm^2
Ob = 3cm + 28cm + 15cm + 20cm = 66cm
B)
P = 1/2 • 15cm • (40cm + 24cm) = 480cm^2
Ob = 39cm + 40cm + 24cm + 25cm = 128cm
C)
P = 1/2 • 8cm • (9cm + 15cm) = 96cm^2
Ob = 9cm + 10cm + 8cm + 15cm = 42cm
D)
P = 1/2 • 24cm • (32cm + 18cm) = 600cm^2
Ob = 32cm + 40cm + 30cm + 18cm = 120cm
