How do you solve the system $x=y-7$ and $x+8y=2$ using substitution?

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Answer 1 · 2018-03-05T15:50:15

$color(red)(x = -6, y = 1)$

$x = y - 7$ Eqn (1)

$x + 8y = 2$ Eqn (2)

Substituting value of x in terms of y in Eqn (2),

$(y - 7) + 8y = 2$

$9y - 7 = 2$

$9y = 2 + 7 = 9$ or $y = 1$

Substituting value of y in Eqn (1),

$x = 1 - 7 = -6$

How do you solve the system x=y-7x=y-7 and x+8y=2x+8y=2 using substitution?