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

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Answer 1 · 2016-04-24T16:00:24

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

Given:

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

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

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

$49 - 14 y + 6 y = 1$ $49-14y+6y=1$

$49 - 8 y = 1$ $49-8y=1$

$8 y = 48$ $8y=48$

$y = \frac{48}{8} = 6$ $y=48/8 = 6$

$y = 6$ $color(blue)(y=6)$
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Substitute for $y$ $y$ in equation (1)

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

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

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