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How do you solve y = 3x - 4 and y = -2x + 1?

1 Answer

José Roberto Pereira

Oct 17, 2015

$x = 1$ $x=1$
$y = - 1$ $y=-1$

Explanation:

$y = 3 x - 4$ $y=3x-4$ (1)
$y = - 2 x + 1$ $y=-2x+1$ (2)

Subtracting (1) - (2):

$0 = 5 x - 5$ $0 = 5x-5$

$5 x = 5$ $5x=5$

$x = \frac{5}{5} = 1$ $x=5/5=1$

$y = 3 \times 1 - 4 = - 1$ $y=3xx1-4=-1$

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