You are adding s^2 to your 128 ft^2. s^2 is a common representation of a square. So you could think of it as adding an area of a square of side "s" to your deck.
So one way of drawing it is to draw a rectangle with area 128 ft^2 and attaching a square to one of its side. The square that is attached has a side lenght of "s."
Answer: amplitude
Step-by-step explanation: The amplitude represents half the distance between the maximum of a sine or cosine graph.
0.584 is greater than 0.58 !