For a square with a side length of 10cm, draw a circle with a radius of 10cm on the opposite vertex. What is the overlapping area of the middle? Ask for the formula, don't send the answer directly

For a square with a side length of 10cm, draw a circle with a radius of 10cm on the opposite vertex. What is the overlapping area of the middle? Ask for the formula, don't send the answer directly

1/2×10²×π-10²=50π-100cm²