x + 50 + 600 = 850
x + 50 = 850 - 600
x + 50 = 250
x = 250 - 50
x = 200
x+50+600=850
x+50=850-600
x+50=250
x=250-50
x=200
x = 850 - 600 - 50
x = 200
tk mk nhé xin bạn đó mà!!!!!
x + 50 + 600 = 850
x + 650 = 850
x = 850 - 650
x = 200
x + 50 + 600 = 850
x + 650 = 850
x = 200
vậy: x = 200