Answer:
Option C. 4(20-16y): Each side measures 20-16y units.
Step-by-step explanation:
we know that
The perimeter of a square is equal to
[tex]P=4b[/tex]
where
b is the length side of the square
we have
[tex]P=(80-64y)\ units[/tex]
substitute the given value in the formula
[tex](80-64y)=4b[/tex]
solve for b
Divide by 4 both sides
[tex](20-16y)=b[/tex]
Rewrite the expression
[tex]b=(20-16y)\ units[/tex]
Alternative Method
we have
[tex]P=(80-64y)\ units[/tex]
Factor 4
[tex]P=4(20-16y)\ units[/tex]
so
Each side measures (20-16y) units.