x + x + 56 + 100 = 56 + 200
2x + 156 = 256
2x = 256 - 156
2x = 100
x = 50
x+x+56+100=56+200
2x+156=256
2x =100
x =50
vậy x=50
ai tk mk, mk tk lại, hứa luôn,..
x + x + 56 + 100 = 56 + 200
2x + 156 = 256
2x = 256 - 156
2x = 100
x = 50
x + x + 56 +100=56+200
x2+56+100=256
x2+56=256-100
x2+56=156
x2=156-56
x2=100
x2=102
x=10
mình nha, mik nhanh nhất.