Answer:
[tex] \boxed{x = 11} [/tex]
Explanation:
[tex]y = 3 - x \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: - equation _{1}\\ 3x + 4y = 1 \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: - equation _{2} \\ \\ Putting \: value \: of \: y \: in \: equation_{1} \: to \: equation_{2} \\ \\ = > 3x + 4(3 - x) = 1 \\ \\ = > 3x + (4 \times 3) - (4 \times x) = 1 \\ \\ = > 3x + 12 - 4x = 1 \\ \\ = > - x + 12 = 1 \\ \\ = > - x = 1 - 12 \\ \\ = > \cancel{- }x = \cancel{ - }11 \\ \\ = > x = 11[/tex]