How do you solve the following system?: $9y = -3x - 9 , 5x + 3y = -3$

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Answer 1 · 2018-04-07T14:28:04

Substitution/Elimination/Graphing Method

Using the substitution method, starting with the first equation:

$9y = -3x-9$

$9y+9 = -3x$

$(9y)/-3+9/-3 = (-3x)/-3$

$x = -3y -3$

Substituting $(x=-3y-3)$ into the second equation to find $y$ :

$5x+3y = -3$

$5(-3y-3) + 3y=-3$

$-15y-15 + 3y=-3$

$-12y=12$

$y=-1$

Now substituting $(y=-1)$ into second equation to find $x$ :

$5x+3y = -3$

$5x+3(-1)=-3$

$5x-3 = -3$

$5x= 0$

$x =0$

Test $(x=0, y=-1)$ in other equation to validate

$9y = -3x-9$

$9(-1) = -3(0)-9$

$-9 = -9$ ,

How do you solve the following system?: 9y = -3x - 9 , 5x + 3y = -3 9y = -3x - 9 , 5x + 3y = -3