Răspuns :
x+x+2.5+2x=12
2x+2.5+2x=12
4x+2.5=12
4x+12-2.5
4x=9.5
x=9.5:4
x=95/10:4
x=19/2:4
x=19/2 x 1/4
x=19/2x4
x=19/8
sau
x=2.375
2x+2.5+2x=12
4x+2.5=12
4x+12-2.5
4x=9.5
x=9.5:4
x=95/10:4
x=19/2:4
x=19/2 x 1/4
x=19/2x4
x=19/8
sau
x=2.375