Respuesta :

[tex]Question \ 1) \ x + 3y = 9[/tex] 

[tex] x=9-3y [/tex]  [tex]|Subtract \ 3y \ from \ both \ sides|[/tex] 

[tex]Question \ 2) \ 3x - 3y = -13[/tex] 

[tex] 3(x-y)=-13 [/tex]   [tex]|Factor \ out \ the \ common \ term \ 3|[/tex]

[tex]x-y= \dfrac{13}{3}[/tex]   [tex]|Divide \ both \ sides \ by \ 3|[/tex]

[tex]x=- \dfrac{13}{3}+y [/tex]  [tex]|Add \ y \ to \ both \ sides|[/tex]

[tex]x=y- \dfrac{13}{3} [/tex]  [tex]|Regroup \ terms|[/tex]