1. a) 6x+3-4x-12=5-4x-2
2x-9=3-4x
2x+4x=3+9
6x=12
x=12/6
x=2
b) 12x-15-6x-21+32=4x+2-14
6x+4=4x-12
6x-4x= -12-4
2x= -16
x= -16/2
x= -8
2. a) 28/100*120 simplifici 100 si 120 cu 4= 28/25*30 simplifici 25 si 30 cu 5=28/5*6=168/5
b) 18/100*325 simplifici 100 si 325 cu 25= 18/4*13= 234/4= 117/2
3. 24/15-36/20+2/15=26/15-9/5 amplificam pe 9/5 cu 3
26/15-27/15= -1/15