Question

Questão2 -Calcule a área de um círculo cujo diâmetro mede 18 cm.​

Answer 1

$> resolucao \\ \\ \\ > area \: do \: circulo \\ \\ \\ r = \frac{d}{2} \\ r = \frac{18}{2} \\ r = 9cm \\ \\ \\ \\ a = \pi \: . \: r {}^{2} \\ a = \pi \: \: 9 {}^{2} \\ a = 81\pi \: cm {}^{2} \\ \\ > > > > >$

Answer 2

$\sf A=\pi\cdot\left(\sf\dfrac{d}{2}\right)^2$

$\sf A=3{,}14\cdot\left(\sf\dfrac{18}{2}\right)^2$

$\sf A=3{,}14\cdot9^2$

$\sf A=3{,}14\cdot81$

$\boxed{\boxed{\sf A=254{,}34\,cm^2}}$