Answer: 5 feet.
Step-by-step explanation:
Remember that the lenghts of the sides of a regular octagon are equal.
You can observe in the figure that the lenght of a side of the regular octagon is 1.25 inches.
Let be "s" the actual length of a side of the regular octagon.
Knowing that the scale drawing has a scale of 1 inch 4 feet, you can find the actual lenght of a side of this regular octagon with:

Therefore, the actual length of a side of the octagon is 5 feet.
If the diameter of the cylinder's base is 10, then the radius is half that, or 5.
Answer: See below:
Advantages as an equation: When you have an equation instead of a graph, you can use the equation to find exact values for a function. With a graph, don't always have the exact values. However, with an equation, you can find the exact input or output values.
Disadvantages as an equation: You don't get to see the overall picture or patterns in the function. With a graph, you can easily see the increasing and decreasing intervals of the function.