Answer:
(-2,-3)
Step-by-step explanation:
Put the equations over each other.
[tex] \binom{x - y = 1}{ - x + 3y = - 7 } [/tex]
Subtract the x values.
[tex] \binom{ - y = 1}{3y = - 7} [/tex]
Subtract on both sides.
[tex]2y = - 6[/tex]
Divide on both sides.
[tex]y = - 3[/tex]
Insert the y value into one of the equations.
[tex]x - ( - 3) = 1[/tex]
Get rid of the parenthesis.
[tex]x + 3 = 1[/tex]
Subtract on both sides.
[tex]x = - 2[/tex]
You could also individually plug in each solution into both equations to see if they are true.