How do you solve $5 x - y = 20$ $5x-y =20$ and $6 x + 49 = y$ $6x+49 =y$ using substitution?

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Answer 1 · 2017-08-30T06:44:51

$x = - 69$ $x=-69$
$y = - 365$ $y=-365$

Given -

$5 x - y = 20$ $5x-y=20$ ---------------------(1)
$6 x + 49 = y$ $6x+49=y$ ---------------------(2)

Substitute $y = 6 x + 49$ $y=6x+49$ in equation (1)

$5 x - (6 x + 49) = 20$ $5x-(6x+49)=20$
$5 x - 6 x - 49 = 20$ $5x-6x-49=20$
$- x = 20 + 49 = 69$ $-x=20+49=69$
$x = - 69$ $x=-69$

Substitute $x = - 69$ $x=-69$ in equation (2)

$y = 6 (- 69) + 49$ $y=6(-69)+49$
$y = - 414 + 49 = - 365$ $y=-414+49=-365$
$y = - 365$ $y=-365$

How do you solve 5x−y=205x-y =20 and 6x+49=y6x+49 =y using substitution?