Răspuns:
Explicație pas cu pas:
4x-y=11
7x-5y=16
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y = 4x - 11
7x - 5(4x - 11) = 16
7x - 20x + 55 = 16
-13x + 55 = 16
13x = 55 - 16
13x = 39
x = 39 : 13 = 3
y = 4*3 - 11 = 12 - 11 = 1
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x=2y-1
2x+3y=12
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2(2y - 1) + 3y = 12
4y - 2 + 3y = 12
7y = 12 + 2 = 14
y = 14 : 7 = 2
x = 2*2 - 1 = 4 - 1 = 3