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

1 Answer

José Roberto Pereira

Oct 17, 2015

$x = 2$ $x=2$
$y = 6$ $y=6$

Explanation:

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

Subtracting (1) - (2):

$0 = 2 x - 4$ $0 = 2x-4$

$2 x = 4$ $2x=4$

$x = \frac{4}{2} = 2$ $x=4/2=2$

$y = 3 \times 2 = 6$ $y=3xx2=6$

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