#### Answer

The area of the walkway is $(16x+64) ft^{2}$.

#### Work Step by Step

Find the total area of the patio and walkway.
$(x+8)^{2}$
...square the binomial.
$=x^{2}+2(x)(8)+8^{2}$
...simplify.
$=x^{2}+16x+64$
Find the area of the patio
The area of the patio is $x\cdot x$, or $x^{2}$.
Find the area of the walkway.
Area of walkway=Total area - Area of patio
$A=(x^{2}+16x+64)-x^{2}$
$=(x^{2}-x^{2})+16x+64$
...add like terms.
$=16x+64$
The area of the walkway is $(16x+64) ft^{2}$.