Pls help with math asap

[tex] \large{ \text{Hi, Hope you are fine!}}[/tex]
[tex] \bull \: \: \: \sf{\angle CGE= x \degree}[/tex]
[tex] \bull \: \: \: \sf{ \angle AGF = 75 \degree}[/tex]
[tex] \bull \: \: \: \sf{AGC=90 \degree}[/tex]
[tex] \bull \: \: \: \sf{Value \: of \: x}[/tex]
[tex] \sf{\angle AGC + \angle AGD=180° (Linear \: pair)}[/tex]
[tex] \sf{:\implies90 \degree+ \angle AGD=180° }[/tex]
[tex] \sf{ :\implies\angle AGD=180° - 90 \degree}[/tex]
[tex] \sf{:\implies \angle AGD= 90 \degree}[/tex]
[tex] \sf{:\implies\angle FGD= \angle CGE=x}[/tex]
[Vertically opposite angle]
[tex] \sf{ \angle AGD= 90 \degree}[/tex]
[tex] \sf{:\implies \angle AGF+ \angle FGD= 90 \degree}[/tex]
[tex] \sf{ :\implies75 \degree + x = 90 \degree}[/tex]
[tex] \sf{ :\implies x = 90 \degree - 75 \degree}[/tex]
[tex] \sf{ :\implies \: x = 15 \degree}[/tex]