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The statement $p:$ For any real numbers $x, y$ if $x=y$, then $2 x+a=2 y+a$ when $a \in \mathrm{Z}$.
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The correct answer is:
is true
We prove the statement $p$ is true by contrapositive method and by direct method.
Direct method: For any real number $x$ and $y$,
$\begin{array}{l}
x=y \\
\Rightarrow 2 x=2 y \\
\Rightarrow 2 x+a=2 y+a \text { a for some } a \in Z
\end{array}$
Contrapositive method: The contrapositive statement of $p$ is "For any real numbers $x, y$ if $2 \mathrm{x}+\mathrm{a} \neq 2 \mathrm{y}+\mathrm{a}$, where $\mathrm{a} \in \mathrm{Z}$, then $\mathrm{x} \neq \mathrm{y}$."
Given, $2 x+a \neq 2 y+a$
$\begin{array}{l}
\Rightarrow 2 x \neq 2 y \\
\Rightarrow x \neq y
\end{array}$
Hence, the given statement is true.
Direct method: For any real number $x$ and $y$,
$\begin{array}{l}
x=y \\
\Rightarrow 2 x=2 y \\
\Rightarrow 2 x+a=2 y+a \text { a for some } a \in Z
\end{array}$
Contrapositive method: The contrapositive statement of $p$ is "For any real numbers $x, y$ if $2 \mathrm{x}+\mathrm{a} \neq 2 \mathrm{y}+\mathrm{a}$, where $\mathrm{a} \in \mathrm{Z}$, then $\mathrm{x} \neq \mathrm{y}$."
Given, $2 x+a \neq 2 y+a$
$\begin{array}{l}
\Rightarrow 2 x \neq 2 y \\
\Rightarrow x \neq y
\end{array}$
Hence, the given statement is true.
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