[tex]Suppose \ x= Width\\
Then \ length\ of \ rectangle=16-2x\\
Now \ suppose \ Area=A \\
[/tex]
Formula for area of rectangle:
Area= Length x width
Put values
[tex]A(x)= x \times \ (16-2x) \\
A(x)=16x-2 x^{2} \\
A(x)=-2 x^{2} +16x[/tex]
Answer: A(x)= -2x²+16x
