Răspunsuri

2014-10-19T16:14:08+03:00
A+b+c=18
2a+b+2c=25
se aduna cele 2 ecuatii si rezulta
3a+2b+3c=43
(a+c)*(3a+2b+3c)=(a+c)*43
(a+c)*43=0
a+c=0