Question

4b+3c=17
3b+2c=12 va rog am incercat si nu-mi iese

Answer 1

4b+3c=17    inmultim cu 3
3b+2c=12    inmultim cu -4

12b+9c=51
-12b-8c=-48  adunam
c=3
b=(12-2x3)/3=2

Answer 2

4b+3c=17
3b+2c=12
3b=12-2c=>
b=12-2c/3 inlocuim in prima ecuatie
4x(12-2c/3)  +3c=17
48-8c/3+3c=17
48-8c+9c/3=17
48+c=17x3
c=51-48
c=3
b=12-2x3/3
b=6/3
b=2
verificare
4b+3c=17
4x2+3x3=17
8+9=17
3b+2c=12
3x2+2x3=12
6+6=12
deci c=3,b=2