Can someone me? i've tried my notes but it seems to not work.

The area of the shaded area is 540 cm^2.

Step-by-step explanation:

To find the area of the shaded area, we will need to find the area of eight congruent triangles. To find the width of one of the triangles(they are all congruent), we can use the equation [80 - (22 + 22)]/4, which equals 9. Now, to find the length of a triangle, we divide 30 by 2, and we get 15. Finally, we multiply 15 by 9 then divide two get the area of one triangle, which is 67.5, then multiply that by eight, and we get a final answer of 540, or 540 cm^2.