Answer:
A
Explanation:
We assume this playground is a rectangle. The area of a rectangle is of the form: A = lw, where l is the length and w is the width.
Here, the length is l = x and the width is w = x + 3. So, plug these in:
A = lw
A = x(x + 3)
Expand this out:
A = x² + 3x
The answer is thus A.