Answer: 
Step-by-step explanation:
1. You know that:
- The roped-off area whose width is represented with <em>x,</em> it is created around a rectangular museum.
- The dimensions of the rectangular museum are: 30 ft by 10 ft.
- The combined area of the display and the roped-off area is 800 ft².
2. The area of the rectangular museum can be calculated with:

Where
is the lenght and
is the width.
You have that the lenght and the width in feet are:

3. Let's call
the width of the roped-off area. Then, the combined area is:

Where



4. Substitute values and simplify. Then:


Step-by-step explanation:
From your problem statement, I believe the equation will look like this:

The slash means "divided by" -- you should use division to solve this equation.
For division involving exponents with the same base, you can use the following rule:

Subtituting
for
,
for
and
for
, we get the following:

The equation in slope intercept for is y = 5/2x + 4
The y intercept is 4
Answer:


And the margin of error with this one:


Step-by-step explanation:
Assuming that the parameter of interest is the sample mean
. And we can estimate this parameter with a confidence interval given by this formula:
(1)
For this case the confidence interval is given by (1.9, 3.3)
Since the confidence interval is symmetrical we can estimate the sample mean with this formula:


And the margin of error with this one:

