Răspuns :
3x+4.2=4.9 // -4.2
3x=0.7 //:3
x=0.7/3=0.2(3)
5x-3=7x+27.9 (ducem totul intr-o parte)
-2x-30.9=0
2x=-30.9
x=-30.9/2=15.45
3x=0.7 //:3
x=0.7/3=0.2(3)
5x-3=7x+27.9 (ducem totul intr-o parte)
-2x-30.9=0
2x=-30.9
x=-30.9/2=15.45
[tex]a).3x+4,2=4,9 \\ 3x=4,9-4,2 \\ 3x=0,7 \\ x=0,7:3 \\ x=0,2(3) \\ b).5x-3=7x+27,9 \\ 5x-7x=27,9+3 \\ -2x=30,9 \\ x=-15,45[/tex]