39 + 19 + x = 74
19 + x = 74 - 39
19 + x = 35
x = 35 - 19
x = 16
tk nha
39 + 19 + x = 74
58 + x = 74
x = 74 - 58
x = 16
Vậy x = 16
Chúc cậu hok giỏi
39 + 19 + x = 74
58 + x = 74
x = 74 - 58
x = 16
39 + 19 + x = 74
58 + x = 74
x = 74 - 58
x = 16
39 + 19 + x = 74
58 + x = 74
x = 74 - 58
x = 16
39 + 19 + x = 74
58 + x = 74
x = 74 - 58
x = 16