<=> abc + 1111 = abc x 10 x 4
<=> 1107=abcx9
<=>1107: 9=abc
<=> abc=123
nha bn
abc+1111=abc4
abc+1111=abc x 10 + 4
abc x 10 - abc=1111-4
9 x abc = 1107
abc=1107:9
abc=123
k nha
Ta có :
abc+1111=abc4
=x10abc=1111-1=1107
x9abc=abc=1107/9
abc = 123
abc+1111=abc4 abc+1111=abc*9 abc=1111:9 abc=123