2000019106
Level:
C
Consider the following equation with a parameter \( a\).
\[
\frac{x-a}{x-3}=2a
\]
Choose the table that summarizes solutions of the equation according to the value of \(a\).
\(\begin{array}{cc} \hline \text{Parameter} & \text{Solution set}\\ \hline
a \in \left\{\frac12;3\right\} & \emptyset \\
a \in \mathbb{R} \setminus \left\{\frac12;3\right\}& \left\lbrace\frac{5a}{2a-1}\right\rbrace
\\\hline \end{array}\)
\(\begin{array}{cc} \hline \text{Parameter} & \text{Solution set}\\ \hline
a =3 & \emptyset \\
a \neq 3& \left\lbrace\frac{5a}{2a-1}\right\rbrace
\\\hline \end{array}\)
\(\begin{array}{cc} \hline \text{Parameter} & \text{Solution set}\\ \hline
a=\frac12 & \emptyset \\
a \neq \frac12 & \left\lbrace\frac{5a}{2a-1}\right\rbrace
\\\hline \end{array}\)