Known circle area is 9.42 square centimeter, seek shadow part area A graph is a circle. There is a square in the quarter circle. Find the area beyond the quarter circle

Known circle area is 9.42 square centimeter, seek shadow part area A graph is a circle. There is a square in the quarter circle. Find the area beyond the quarter circle

9.42÷3.14-9.42×1/4
=3-2.355
=645 square centimeter