Răspuns :
x=bursa
450-x = 2x-450
3x=900
x=300 lei
verificare
450-300=150
300x2=600
600-450=150
450-x = 2x-450
3x=900
x=300 lei
verificare
450-300=150
300x2=600
600-450=150
[tex]Rezolvare: 450-a=2*a-450 \\ 2a+a=450+450 \\ 3a=900 \\ a=900:3 \\ a=300~lei \\ a=bursa[/tex]