Question

Ex 5 va rog! Dau multe puncte

Answer 1

4A +5S =81  l *3
6A+7S =115  l*2

12A+15S =243    ( LE SCADEM)
12A+14S =230
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 /       1S =13  lei
4A+5*13 =81
4A=81-65 =16
A =4 lei 

 2A+3S =2*4+3*13=8+39=57

Answer 2

4a+5s=81 lei  *3
6a+7s=115 lei  *2

12a+15s=243
12a+14s=230
243-230=13

1s=13lei
4a+5x13=81
4a=81-65=16
4a=16:4
4a=4 lei

2a+3s=2x4+3x13=8+39=47 lei plateste