Răspuns :
a+b=12920
a-b=12900
a=12900+b
12900+b+b=12920
2b=12920-12900
2b=20
b=10
a=12900+10
a=12910
a-b=12900
a=12900+b
12900+b+b=12920
2b=12920-12900
2b=20
b=10
a=12900+10
a=12910
a+b=12920
a-b=12900 => a=b+12900
a |—|+12900|
b |—|
12920-12900=20
20:2=10 ( b )
10+12900=12910
Proba :
12910+10=12920
12910-10=12900
a-b=12900 => a=b+12900
a |—|+12900|
b |—|
12920-12900=20
20:2=10 ( b )
10+12900=12910
Proba :
12910+10=12920
12910-10=12900