x + 10 = 30 + 20
x + 10 = 50
x = 50 -10
x =40
x + 10 = 30 + 20
x + 10 = 50
x = 50 - 10
x = 40
x + 10 = 30 + 20
x + 10 = 50
x = 50 - 10
x = 40
Vậy x = 40
x+10=30+20
x+10=50
x=50-10
x=40
x+10=30+20
x+10=50
x=50-10
x=40
=>x can tim la:40
x+ 10 = 30+ 20
=> x+ 10 = 50
=> x= 40
đáp số x= 40