Chapter 3 - Equations and Problem Solving - 3.1 - Solving First-Degree Equations - Concept Quiz 3.1 - Page 100: 10

True

The transitive property states that "if $a=b$ and $b=c$, then $a=c$". Therefore, the question statement 'if $x=y$ and $y=4$, then $x=4$' is indeed correct according to the transitive property. This means that the question statement is true.