405+x=1000-158 y-457=56+104 x-209=400-264 239+y=800-197

Question

405+x=1000-158
y-457=56+104
x-209=400-264
239+y=800-197

Answer 1

405+437=842
617-457=160
345-209=136
239+364=603

Answer 2

1) x=437
2) y=617
3) x=345
4) y=366