Question

4x + y = 14
2x - y = 10​

Answer 1

Resposta:

4x + y = 14

$x = \frac{10 + y}{2} \\ x = \frac{10 + ( - 2)}{2} \\ x = \frac{8}{2} = \\ x = 4$

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2x - y = 10

$2x = 10 + y \\ x = \frac{10 + y}{2}$

$4( \frac{10 + y}{2} ) + y = 14 \\ \frac{40 + 4y}{2} + y = 14 \\ 40 + 4y + 2y = 28 \\ 40 + 6y = 28 \\ 6y = 28 - 40 \\ 6y = - 12 \\ y = \frac{ - 12}{6} \\ y = - 2$