Question

x+y=4 5x-2y=-1 me ajudem

Answer 1

Para zerar o X

$5x - 2y = - 1$

$x + y = 4 \: \times ( - 5)$

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$5x - 2y = - 1$

$- 5x - 5y = - 20$

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$0x - 7y = - 21$

$y = \frac{ - 21}{ - 7}$

$y = 3$