Răspunsuri

2014-10-08T22:58:59+03:00
Deci problema asta am facut-o azi in clasa si am iesit la tabla.

2a+b+2c=25
a+b+c=18
25-18=7 (a+c)

2a+b+2c=25
a+b+c=18
25+18=43 (3a+2b+3c)

(a+c) x (2a+b+2c) = 7x43 = 301 
21 4 21