subtracting the second equation from the first can be done below
[tex]\begin{gathered} -3x+2y=7 \\ -3x-2y=4 \\ \\ -3x-(-3x)=0 \\ 2y-(-2y)=4y \\ 7-4=3 \\ 4y=3 \\ y=\frac{3}{4} \\ \\ -3x+2(\frac{3}{4})=7 \\ -3x+\frac{6}{4}=7 \\ -3x=7-\frac{3}{2} \\ -3x=\frac{14-3}{2} \\ -3x=\frac{11}{2} \\ -6x=11 \\ x=-\frac{11}{6} \end{gathered}[/tex]