Răspuns :
2x+7 = 4x-5 | +5 2x+9 = 3(2x-1)
2x+7+5= 4x-5+5 2x+9 = 6x-3 | -9
2x + 12 = 4x | -2x 2x+9-9 = 6x-3-9
2x-2x+2= 4x-2x 2x = 6x - 12 |-2x
1 2 = 2x | ;2 0 = 4x -12 | +12
x = 6 12 = 4x |:4
3 = x
2x+7+5= 4x-5+5 2x+9 = 6x-3 | -9
2x + 12 = 4x | -2x 2x+9-9 = 6x-3-9
2x-2x+2= 4x-2x 2x = 6x - 12 |-2x
1 2 = 2x | ;2 0 = 4x -12 | +12
x = 6 12 = 4x |:4
3 = x