problema

1^ RIGA:

p =13 + 14 + 15 = 42 ; Α = √(21·(21 - 13)·(21 - 14)·(21 - 15))   ---->Α = 84

2^ RIGA:

p=16 + 30 + 34 = 80 ; Α = √(40·(40 - 16)·(40 - 30)·(40 - 34))--->Α = 240

3^RIGA:

c =144 - (60 + 36) = 48; Α = √(72·(72 - 60)·(72 - 36)·(72 - 48))--->Α = 864

4^ RIGA:

a = 126 - (42 + 45) = 39: Α = √(63·(63 - 39)·(63 - 42)·(63 - 45))----> Α = 756