Question

Ex 6 va rog!!!Dau coroana si 25 de puncte!!!

Answer 1

$\it a)\ \mathcal{A}_{disc}=\pi R^2=100\pi|_{:\pi}\Rightarrow R^2=100=10^2 \Rightarrow R=10\ cm\\ \\ L_c=2\pi R=2\pi\cdot10=20\pi\ cm\\ \\ b)\ \mathcal{A}_{disc}=\pi R^2=196\pi|_{:\pi}\Rightarrow R^2=196=14^2 \Rightarrow R=14\ cm\\ \\ L_c=2\pi R=2\pi\cdot14=28\pi\ cm$