5. a) 3x+5-2x-4=8-3x+3 x+1=11-3x 4x=10 x=2,5 b) 6x+3-4x-12=5-4x-2 2x-9=3-4x 6x=12 x=2 8. 6n+13/(8n+17)×2 6n+13/(6n+13)×3 6n+13/(16n+39)-(16n+34) 6n+13/5 6n+13€{1,5} 6n€{-12,-8} n€{-2} cum n€nr nat înseamnă ca nu are sol 9. a) 148x-259=125x-75 23x=184 x =8