$ =\frac{10 \times10}{2}=50cm^2 $2/ حاصل ضرب قطرها = مساحت مربع $ = \frac{7}{16} = \frac{x}{50} \Rightarrow x = \frac{50 \times 7}{16} = \frac{350}{16} = 21/875 \simeq 22 cm^2 $