[tex]\displaystyle \left \{\begin{array}{ccc} 2y=x-12 \\\\y=2x^2+3x-4 \end{array } \right. \Rightarrow \begin{cases} y =\dfrac{x-12}{2} \\\\ 2x^2+3x-4=\dfrac{x-12}{2} \end{cases } \Rightarrow \\\\\\ 2x^2+3x-4=\frac{x-12}{2} \\\\4x^2+6x-8=x-12 \\\\4x^2+5x+4=0 \\\\ \rm D=25-4\cdot 4\cdot 4=-39 \\\\D<0 \ \displaystyle \Rightarrow\varnothing \\\\Answer : \large \boldsymbol{} \sf (x ; y) \notin \mathbb R[/tex]
