Since:
[tex]\Delta ABC\cong\Delta DEF[/tex]
We can use CPCTC ( Corresponding parts of congruent triangles are congruent) so:
[tex]\begin{gathered} m\angle A=m\angle D \\ 60=5y \\ so\colon \\ y=\frac{60}{5} \\ y=12 \end{gathered}[/tex][tex]\begin{gathered} 6x-4=3x+26 \\ 6x-3x=26+4 \\ 3x=30 \\ x=\frac{30}{3} \\ x=10 \end{gathered}[/tex]
