## Answer :

[tex]\boxed{\boxed{x=30~in}}[/tex]

and

[tex]\frac{3}{2}=\frac{18}{y}[/tex]

[tex]y=12~in[/tex]

[tex]Maximum~~height~~=~~12+18+30~~=~~60~in[/tex]

them

[tex]1~in=\frac{1}{12}~ft[/tex]

[tex]60~in=5~ft[/tex]

[tex]\boxed{\boxed{\boxed{\therefore~Maximum~~height~~=~~60~in~~=~~5~ft}}}[/tex]