We can rearrange the first equation (x - y = -3) to be
[tex] y = x + 3 [/tex] (from adding y to both sides then adding 3 to both sides)
we can plug (x + 3) for the y in the second equation
and get
[tex] x + 3(x + 3) = 5[/tex]
we can distribute that 3
[tex] x + 3x + 9 = 5 [/tex]
add like terms
[tex] 4x + 9 = 5 [/tex]
subtract 9 from both sides
[tex] 4x = -4 [/tex]
divide both sides by 4
[tex] x = -1 [/tex]
therefore your answer would be [tex] x = -1 [/tex]
