Răspuns:
costul telefonului- x
costul tabletei- y
in total- 900lei
(sistem): x+y=900. x=900-y. x=900-y
y-x=150=> y-(900-y)= 150. y-900+y=150
x=900-y. x= 900-y. x=900-y. x=375
2y=150+900=> 2y=1050=> y=525=> y=525
raspuns: telefonul costa 375lei iar tableta- 525lei. eu mam staruit
