The answer for x is 9. Hope this helps. See work below.
Answer:
We can write:
x + y = -2
xy = -80
We can rewrite the first equation as x = -y - 2 and then plug that into the second equation to get (-y-2) * y = -80 → -y² - 2y = -80 → y² + 2y - 80 = 0 → (y - 8)(y + 10) = 0 → y = 8, -10. Substituting these values into the first equation we get x = -10, 8 so the answer is (x₁, y₁) = (-10, 8) or (x₂, y₂) = (8, -10).
$6662.50
4.75% = $237.50
$237.50 x 7 = $1662.50
$5000 + $1662.50 = $6662.50
Answer = $6,662.50
Answer:
a) Figure attached
b) If we see the scatter plot we can conclude that the possible relation between x and y is linear and with a positive correlation since when the values of x increases the values for y increases as well.
c) 
We can find the numerator like this:

And then:

d)
Step-by-step explanation:
Part a
For this part we use excel in order to create the scatterplot and we got the result on the figure attached.
Part b
If we see the scatter plot we can conclude that the possible relation between x and y is linear and with a positive correlation since when the values of x increases the values for y increases as well.
Part c
The sample covariance is defined as:

We can find the numerator like this:

And then:

Part d
The correlation coefficient is a "statistical measure that calculates the strength of the relationship between the relative movements of two variables". It's denoted by r and its always between -1 and 1.
And in order to calculate the correlation coefficient we can use this formula:
For our case we have this:
n=5
So then the correlation coefficient would be r =0.693