How do you solve $7x + 6y = 1$ and $x = 7 - 2y$ using substitution?

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Answer 1 · 2016-04-24T16:00:24

Point of intersection $" "->(x,y) = (-5,6)$

Given:

$x=7-2y$ ............................(1)
$7x+6y=1$ .........................(2)

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Substitute for $x$ in equation (2) using equation (1)

$=> 7x+6y=1" "->" "7(7-2y)+6y=1$

$49-14y+6y=1$

$49-8y=1$

$8y=48$

$y=48/8 = 6$

$color(blue)(y=6)$
'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Substitute for $y$ in equation (1)

$x=7-2y" "->" "x=7-2(6)$

$color(blue)(x=-5)$
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Tony B

How do you solve 7x + 6y = 17x + 6y = 1 and x = 7 - 2yx = 7 - 2y using substitution?