Odpowiedź:
[tex]P_{AFCE}= 40 cm^{2}[/tex]
Szczegółowe wyjaśnienie:
[tex]BF=\frac{2}{5} * BC = \frac{2}{5}*10 cm=4cm[/tex]
[tex]AE=\frac{1}{5} * AD = \frac{1}{5}*10 cm=2cm[/tex]
[tex]P_{AFCE}= P_{ABCD}-(P_{DCE}+P_{ABF})[/tex]
[tex]P_{AFCE}=10*10-(\frac{1}{2}*10*8+\frac{1}{2}*10*4 )=100-60=40cm^{2}[/tex]
