800 - x = 879 - 610
800 - x = 269
- x = 269 - 800
- x = - 531
x = 531
800-x=879-610
800-x=269
x=800-269
x=531
800 - x = 879 - 610
800 - x = 269
- x = 269 - 800
- x = - 531
x = 531
800-x=879-610
800-x=269
x=800-269
x=531