we have a circle first we will calculate the whole area of the circle using the next formula
![A=\pi r^2](https://img.qammunity.org/2023/formulas/mathematics/high-school/lcgfavc89jro4qntamn2b9gfliomu1jwuf.png)
where r= 13 units
![A=\pi(13)^2=530.93\text{ square units}](https://img.qammunity.org/2023/formulas/mathematics/college/5ajic41zm9ts9xqbioahgnw0f2thbl6xq2.png)
Then we have 54° we need to divide between 360 In order to know the part of the circle we have
![(360)/(54)=(20)/(3)](https://img.qammunity.org/2023/formulas/mathematics/college/k6whmcgzypbnsjcd9ganggha183t0dy9gn.png)
so in order to know the area of the sector HJK we will divide the area between 20/3
![A_S=(A)/((20)/(3))=(530.93)/((20)/(3))=79.63](https://img.qammunity.org/2023/formulas/mathematics/college/hz6uwiixkzn91bq68nyt754yfhreivceon.png)