\(x-y=15\Rightarrow x=15+y\)
\(\dfrac{x-4}{y-3}\)\(=\dfrac{4}{3}\)
\(\Rightarrow3x-12=4y-12\)
\(\Rightarrow3x=4y\)
\(\Rightarrow3\left(15+y\right)=4y\)
\(\Rightarrow45+3y=4y\)
\(\Rightarrow y=45\)
\(\Rightarrow x=45+15=60\)
Vậy..................