How do you solve the system of equations $-3x-4y=0$ and $y = -5x - 17$ ?

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Answer 1 · 2017-12-31T20:24:20

$x = -4$
$y = +3$

$-3x-4y=0$
$y=-5x-17$

Substitute the second term of the second equation to the first one:
$-3x-4(-5x-17)=0$
$y=-5x-17$

Solve the first one:
$-3x+20x+68=0$
$y=-5x-17$

$17x+68=0$
$y=-5x-17$

$17x=-68$
$y=-5x-17$

$x=-4$
$y=-5x-17$

Substitute $-4$ to the $x$ in the second equation:
$x=-4$
$y=-5(-4)-17$

$x=-4$
$y=20-17$

Result:
$x=-4$
$y=3$

How do you solve the system of equations -3x-4y=0-3x-4y=0 and y = -5x - 17y = -5x - 17?