Răspunsuri

2014-08-27T12:01:50+03:00
Prima ecuatie
2x+7=15 
=> x=4
a doua ecuatie
   3x-11=21
 => x=10/3
a treia ecuatie
  5 + 2(x-1)=12 
=> 2x=9 => x=9/2
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