Question Number 186442 by Mingma last updated on 04/Feb/23
Answered by HeferH last updated on 04/Feb/23
Commented by HeferH last updated on 04/Feb/23
$$\left(\frac{\mathrm{11}}{\mathrm{2}}\right)^{\mathrm{2}} −{r}^{\mathrm{2}} \:=\:{r}^{\mathrm{2}} −\mathrm{4}\:+\:\left(\frac{\mathrm{3}}{\mathrm{2}}\right)^{\mathrm{2}} \\ $$$$\:{r}^{\mathrm{2}} \:=\:\mathrm{16} \\ $$$$\:{Yellow}\:=\:\frac{{r}^{\mathrm{2}} \pi}{\mathrm{2}}\:=\:\mathrm{8}\pi\:{u}^{\mathrm{2}} \\ $$
Answered by mr W last updated on 04/Feb/23
$${r}^{\mathrm{2}} =\frac{\left({a}+{b}+{c}\right){b}+\mathrm{2}{ac}}{\mathrm{4}} \\ $$$$\:\:\:=\frac{\left(\mathrm{5}+\mathrm{4}+\mathrm{2}\right)×\mathrm{4}+\mathrm{2}×\mathrm{5}×\mathrm{2}}{\mathrm{4}}=\mathrm{16} \\ $$$${yellow}\:{area}=\frac{\pi{r}^{\mathrm{2}} }{\mathrm{2}}=\mathrm{8}\pi \\ $$