Odpowiedź:
a)
[tex]P =\frac{1}{2} * 8 * 12 = 48\ cm^{2}[/tex]
b)
[tex]P = \frac{9 + 7}{2} * 4 = 32\ dm ^{2}[/tex]
c)
[tex]P = \frac{1}{2} * 13 * 7 = 45,5\ m^{2}[/tex]
d)
[tex]P = \frac{1}{2}*9*5 = 22,5\ cm^{2}[/tex]
e)
[tex]P = \frac{9,5 + 4,5}{2}*6 = 42\ dm^{2}[/tex]