Răspuns:
Explicație pas cu pas:
a) 3x+5=2 3x=-3 x=-1
b) 5x+3x+18=7x+13 x=-18+13 x=-5
c)2(7x-2)=6(5x+1) 14x-4=30x+6 16x=10 x=0,625
2.
2x-y=1 (2) 4x-2y=2
x+2y=8 x+2y=8
........................
5x=10 x=2 y=2×2-1 y=3
3x+2y=8
-x-2y=-6
.................
2x=2 x=1 2y=8-3×2=8-6 y=1