Two possiblities.
VZ, and ZV.
Answer: 39 degrees
Step-by-step explanation:
Since the triangle is a right angle
The sum of angles in a right angle is 90degrees
51degrees + A= 90 degrees
A= 90degrees - 51 degrees
A=39 degrees
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
49x^2 - 9 = 0
As there is no x term, we can pretty much guess we have a situation where we factlrise by something known aa difference of two squares, so to factorise it:
49 = 7^2
9 = 3^2
x^2 = (x)^2
so...
(7x - 3)(7x + 3) = 0
7x - 3 = 0 7x + 3 = 0
x = 3/7 x = -3/7
Getting in a relationship and lasting a decade .