Question

I'VE BEEN STUCK IN THIS QUESTION FOR HOURS, HELP!

find the area of the blue sector
give your answer as a fraction in the simplest form
for ex: 1/2π

write down the steps please.

Answer 1

`\bf \textit{area of a sector of a circle}\\\\ A=\cfrac{\theta \pi r^2}{360}\quad \begin{cases} r=radius\\ \theta =angle\ in\\ \qquad degrees\\ ----------\\ r=21\\ \theta =90 \end{cases}\implies A=\cfrac{90\pi \cdot 21^2}{360}`