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$$\begin{aligned} x-y & =y-4+2(4.5-2 x) \\ 4(x+2 y) & =-p+7 y \end{aligned}$$$\newline$In the system of equations, $p$ is a constant. For which value of $p$ is there exactly one solution $(x, y)$ where $x=-1$ ?$\newline$Choose $1$ answer:$\newline$(A) $-5$$\newline$(B) $9$$\newline$(C) Any real number$\newline$(D) None of the above