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Parallelogramma:
lato $\small l_1= 22\,m;$
altezza $\small h_1= 15\,m;$
lato incognito $\small l_2= \dfrac{2p-2·l_1}{2} = \dfrac{84-2×22}{2}= \dfrac{84-44}{2}= \dfrac{40}{2}= 20\,m;$
area $\small A= l_1·h_1 = 22×15 = 330\,m^2;$
altezza $\small h_2= \dfrac{A}{l_2} = \dfrac{330}{20} = 16,5\,m.$
Rettangolo:
area $\small A= h_1·h_2 = 15×16,5 = 247,5\,m^2.$
a = 22 m
ha = 15 m
area A = a*ha = 22*15 = 330 m^2
b = (84-22*2)/2 = 20 cm
hb = A/b = 330/20 = 16,5 cm
area rettangolo = A' = 16,5*15 = 247,5 m^2