Question Number 212690 by Spillover last updated on 21/Oct/24
Answered by mr W last updated on 21/Oct/24
$$\mathrm{10}×\left(\mathrm{2}{n}\right)=\left(\mathrm{2}\sqrt{\mathrm{15}}\right)^{\mathrm{2}} \\ $$$$\Rightarrow{n}=\mathrm{3} \\ $$$$\Rightarrow{R}={n}+\frac{\mathrm{10}}{\mathrm{2}}=\mathrm{8} \\ $$$${painted}\:{area}\:=\pi\left({R}^{\mathrm{2}} −{n}^{\mathrm{2}} \right)=\mathrm{55}\pi \\ $$
Commented by TonyCWX08 last updated on 21/Oct/24
$${What}\:{theorem}\:{is}\:{this}? \\ $$
Commented by mr W last updated on 21/Oct/24
Commented by mr W last updated on 21/Oct/24
$${a}+{b}=\mathrm{2}{R} \\ $$$$\frac{{a}}{{h}}=\frac{{h}}{{b}}\:\Rightarrow{h}^{\mathrm{2}} ={ab} \\ $$