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rezolvati in multimea numerelor rationale, ecuatia:
5(x-2)-3(x-2)=20


Răspuns :

x∈Q

5(x-2)-3(x-2)=20

5x-10-3x+6=20

2x-4=20

2x=24

x=12∈Q

5(x-2)-3(x-2)=20
(5•x-5•2)-(3•x-3•2)= 20
(5x-10)-(3x-6)= 20
5x-10-3x+6= 20
5x-3x= 20+10-6
2x= 30-6
2x= 24
x= 24:2
x= 12.