Question

Daca a+2b=5 si b+2c=91,atunci calculati 5a+13b+6c

Answer 1

b = 1 sau 2.

Daca b = 1:
a+2=5
a = 3
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1+2c=91
2c=90
c = 45

a= 3
b = 1
c = 45
5*3+13*1+45*6
15 + 13 + 270 = 298

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Daca b = 2:
a+4 = 5
a = 1

2 + 2c = 91
c = 91-2
c = 89
89 nu se divide cu 2.

Esti clasa I-IV, nu ai invat cu virgula inca, asa ca b nu are cum sa fie 2.
:)