6,3*(-4/7)-(-4 9/13):(8/13)-(-3/4)
6,3*(-4/7)-(-4 9/13):(8/13)-(-3/4)= - (63*4)/70 +[(4*13+9)/13]*13/8 +3/4= =-3,6 +61/8 +6/8= -3,6+67/8=-3,6+8,375=4,775