Răspuns :
a+ 2b-3c=23
2a+b+ 6c=61
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adunam ambele ecuatii si obtinem
a+ 2b-3c+2a+b+ 6c=23+61
3a+3b+3c=84
3(a+b+c)=84
a+b+c=84/3
a+b+c=28
2a+b+ 6c=61
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adunam ambele ecuatii si obtinem
a+ 2b-3c+2a+b+ 6c=23+61
3a+3b+3c=84
3(a+b+c)=84
a+b+c=84/3
a+b+c=28
a + 2b - 3c = 23
2a + b + 6c = 61
Adunam pe verticala .
⇒ 3a + 3b + 3c = 84
3 ( a + b + c ) = 84
a + b + c = 28
2a + b + 6c = 61
Adunam pe verticala .
⇒ 3a + 3b + 3c = 84
3 ( a + b + c ) = 84
a + b + c = 28