Question

Un cerc cu lungimea de 120cm are aria egală cu

Answer 1

L = 2$\pi$r <=> r = $\frac{L}{2\pi }$ = $\frac{120}{2\pi }$ = $\frac{60}{\pi}$

A = $\pi r^{2}$ <=> $\pi$ x $\frac{60^{2} }{\pi^{2} }$ = $\frac{3600}{\pi}$ $cm^{2}$