Question

реши уравнения
30 + х = 39
39 - х = 9
х - 9 = 30

Answer 1

30+x= 39 
x=39-30
x=9
30+9=39
39=39

Answer 2

x=30+9

Answer 3

x=39

Answer 4

339-9=30

Answer 5

39-9=30

Answer 6

30=30