692+248-[800-(123x2+88x3)]-bx8=300x2+2=−bx8+88x3+123x2+140+−140=300x2+2+−140=−bx8+88x3+123x2=300x2−138=−bx8+88x3+123x2+−123x2=300x2−138+−123x2=−bx8+88x3=177x2−138=−bx8+88x3+−88x3=177x2−138+−88x3=−bx8=−88x3+177x2−138=−bx8/−x8=−88x3+177x2−138/−x8=b=88x3−177x2+138/x8
