Geometry: Write a formal proof, ASAP!!!

[tex] \qquad \qquad \bf \huge\star \: \: \large{ \underline{Answer} } \huge \: \: \star[/tex]
[tex]\textsf{ \underline{\underline{Steps to solve the problem} }:}[/tex]
[tex]\qquad❖ \: \sf \: \angle1 \cong \angle2[/tex]
( by corresponding angle pair )
[tex]\qquad❖ \: \sf \: \angle2 \cong \angle3[/tex]
( given in the question )
[tex] \qquad \large \sf {Conclusion} : [/tex]
[tex]\qquad❖ \: \sf \: \angle1 \cong \angle3[/tex]