Question

Daca 2stilouri si 3 pixuri cos
ta 16 lei ,iar 3stilouri si 2pixuri costa 19 lei ,aflati cat costa un stilou

Answer 1

Răspuns

5 ;

Explicație pas cu pas:

2s+3p = 16 ; 3p = 16-2s  ; p = (16-2s)/3 ; inlocuim p in a doua relatie

3s+2p = 19 ; 3s+2(16-2s)/3 = 19 ; numitor comun 3 ;

9s+32-4s = 57 ; 5s = 57-32 = 25 ; s = 25/5 = 5 lei costa un stilou ;

Answer 2

2st._________3p_________16lei\x3
3st__________2p_________19lei\x2

___________________________
6st__________9p________48lei
6st__________4p________38lei

___________________________
Se anuleaza st 5p. 10 lei

1p=10:5= 2lei

2st_______3x2=6lei_____16 lei( am inlocuit)
2st=6+16=22lei

1st=22:2=11lei