Answer
The area of the rectangle is $w^2+4w$ $\text{yd}^2$
Work Step by Step
Since the length is $4$ more than the width, $w$, we must add $4$ to $w$ to find the length. This gives us a length of $w+4$. The formula for area of a rectangle is $A=lw$, where $l$ is the length and $w$ is the width. We plug in the values for width and length: $A=w(w+4)$
We apply the distributive property: $A=w\cdot w+4w$
To multiply powers with the same base, we add the exponents: $A=w^2+4w$