Răspuns:
Explicație pas cu pas:
Metoda substitutiei
2x + y = 3
x + 3y = 5
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y = 3 - 2x
x + 3(3 - 2x) = 5
x + 9 - 6x = 5
-5x + 9 = 5
5x = 9 - 5
5x = 4
x = 4/5
y = 3 - 2*4/5 = 3 - 8/5 = 15/5 - 8/5 = 7/5
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Metoda reducerii
2x + y = 3
x + 3y = 5
_________
2x + y = 3
-2x - 6y = -10
y - 6y = 3 - 10
-5y = -7
y = 7/5
x = 5 - 3y = 5 - 3*7/5 = 25/5 - 21/5 = 4/5