Answer:
The perimeter is equal to [tex](y+39)\ units[/tex]
Step-by-step explanation:
we know that
The perimeter of the triangle is equal to the sum of the length of its sides.
so
[tex]P=AB+BC+AC[/tex]
substitute the values
[tex]P=(y+7)+18+14[/tex]
[tex]P=(y+39)\ units[/tex]