Final answer:
To represent the area of the patio, which is 216 square feet, the equation is lw = 216, where l is the length and w is the width.
Step-by-step explanation:
The question is asking to write an equation that represents the area of the patio. Since the area is given as 216 square feet, the equation for the area of a rectangle, which is length times width, would be lw = 216, where l represents the length and w represents the width of the patio in feet.