Răspuns :
a+b=28,77
a-b=5,69
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a+b+a-b=28,77+5,69
2a=34.46
a=34,46:2
a=17,23
b=28,77-17,23
b=11,54
a-b=5,69
---------------------
a+b+a-b=28,77+5,69
2a=34.46
a=34,46:2
a=17,23
b=28,77-17,23
b=11,54
a+b=28,77
a-b=5,69 =>a=b+5,69
b+5,69+b=28,77=>2b=28,77-5,69=>2b=17,08=>b=17,08:2=>b=8,54
a=28,77-8,54=>a=20,23
a-b=5,69 =>a=b+5,69
b+5,69+b=28,77=>2b=28,77-5,69=>2b=17,08=>b=17,08:2=>b=8,54
a=28,77-8,54=>a=20,23