Salut!
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Datele problemei :
x = 1780
y = 1968 + 1780
z = (x + y) - 4069
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Rezolvare :
y = 1968 + 1780 => y = 3748
z = (1780 + 3748) - 4069 => z = 5528 - 4069 => z = 1459
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x = 1780
y = 3748
z = 1459
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x + y + z = 1780 + 3748 + 1459 => x + y + z = 7287
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Sper că te-am ajutat!