We are asked to determine the area of the sector of a circle with a redius of 9 meters and an angle of 90 degrees. To do that we will use the following formula:
![A=(1)/(2)r^2\theta](https://img.qammunity.org/2023/formulas/mathematics/college/rkog8g2zcutnhrwp3l2uobo5lbmcgwt8hr.png)
Where:
![\begin{gathered} r=\text{ radius} \\ \theta=\text{ angle in radians} \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/vn7c7x88tra3egwcwpyr4pbkwrwub5t5vj.png)
We have that 90 degrees in radians are equivalent to:
![\theta=(\pi)/(2)](https://img.qammunity.org/2023/formulas/mathematics/college/cimuto9s8d048t1acl10nk5k5213e4yiss.png)
Substituting the values in the formula:
![A=(1)/(2)(9m)^2((\pi)/(2))](https://img.qammunity.org/2023/formulas/mathematics/college/zsc0ex41yojr5zhx7ilu6xd41riz9xpps4.png)
Solving the operations:
![A=(81\pi)/(4)\approx63.62m^2](https://img.qammunity.org/2023/formulas/mathematics/college/vm138ffp0bdsdpa8ylvbfmhz1gn44c8is0.png)
Therefore, the area is approximately 63.62 square meters.