How do you solve the following system: $x - 3y = -1 , 4x+y=-7$ ?

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Answer 1 · 2018-04-08T01:26:40

$x=-22/13$
$y= -9/39$

$x - 3y = -1$
$3(4x + y = -7)$

$x-3y = -1$
$12x+3y = -21$

$13x = -22$
$x = (-22/13)$

$(-22/13) - 3y = -1$
$-1 + 22/13 = -3y$
$(-13+22)/13 = -3y$
$9/13 *1/-3 = y$
$y= -(9/39)$

Answer 2 · 2018-04-08T01:29:47

$x=-22/13$
$y=-3/13$

$x-3y=-1$ --- (1)
$4x+y=-7$ --- (2)

From (1),

$x=3y-1$ --- (3)

Sub (3) into (2)

$4(3y-1)+y=-7$
$12y-4+y=-7$
$13y=-3$
$y=-3/13$ --- (4)

Sub (4) into (3)

$x=3(-3/13)-1$
$x=-22/13$

How do you solve the following system: x - 3y = -1 , 4x+y=-7 x - 3y = -1 , 4x+y=-7 ?