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How do you solve $2 x + y = 7$ $2x+y=7$ and $x + 2 y = 2$ $x+2y=2$ ?

1 Answer

Jun 2, 2018

$x = 4$ $x=4$ and $y = - 1$ $y=-1$

Explanation:

$2 \cdot (2 x + y) - (x + 2 y) = 2 \cdot 7 - 2$ $2*(2x+y)-(x+2y)=2*7-2$

$4 x + 2 y - x - 2 y = 14 - 2$ $4x+2y-x-2y=14-2$

$3 x = 12$ $3x=12$ , so $x = 4$ $x=4$

Thus,

$4 + 2 y = 2$ $4+2y=2$

$2 y = - 2$ $2y=-2$ , so $y = - 1$ $y=-1$

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