Sorry. I don’t get that amount. The diagonal of a 9” square is 12.72. There would be 7 across for width (7x 12.72= 89.04”) and 8 for the length (8x 12.72 = 101.76”). 7x 8=56 blocks you would need to make. I use mathopenref.com “diagonals of a square”. If you scroll down, there is a calculator which is a great link.