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The line x = 2 is vertical. This means that ab is horizontal since they are perpendicular. So, the y coordinate of b must be 1.
If x = 2 bisects ab, then a and b are equal distances from x = 2.
a is 2 - (-4) = 6 units away from x = 2, so b must be 6 units away in the other direction. The x coordinate of b is 6 + 2 = 8.
The coordinate of b is (8, 1)
(0,0) on the coordinate plane is the center (origin)
A null hypothesis illustrates that two variables in the hypothesis have no statistical significance.
The null hypothesis is: 
The regression equation is given as:

The variables are:
and 
The null hypothesis states that, there is no statistical significance between
and
.
This is represented as:

Hence, the null hypothesis is: 
Read more about null hypothesis at:
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