The answer is 0 or 10, E+D-B=0 or 10.
The reasoning is as follows...
C+1=A and A+C=10+B or 9+B, depending on whether there is a carryover from E+D, E+D=B or E+D=10+B. Also A+C>10. So E+D-B=0 or 10.
The following are examples of solutions: 679+65=744; 675+69=744; 782+73=855; 671+62=733; 672+61=733; 893+84=977.