Answer:
3/25
Step-by-step explanation:
Steps to find the equation
1. Find the slope
2. Insert slope into the general equation
3. Find y-intercept
4. Insert -intercept into the equation found in step 2
And you get the equation of the line
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Find the slope
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2y - x = 4
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Rewrite into the form y = mx + c
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2y = x + 4
y = 1/2 x + 2
Slope = 1/2
Perpendicular slope = -2 (negative reciprocal)
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Insert slope into the equation
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y = mx + c
y = -2x + c
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Find y-intercept
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y = -2x + c
At point (1, 2)
2 = -2(1) + c
2 = -2 + c
c = 4
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Insert y-intercept into the equation y = -2x + c
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y = -2x + 4
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Answer: y = -2x + 4
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Pull out the common factor of 
:
Recall that 
:
Rationalize the denominator:
Answer:
d. can be equal to the value of the coefficient of determination (r2).
True on the special case when r =1 we have that 
Step-by-step explanation:
We need to remember that the correlation coefficient is a measure to analyze the goodness of fit for a model and is given by:
![r=\frac{n(\sum xy)-(\sum x)(\sum y)}{\sqrt{[n\sum x^2 -(\sum x)^2][n\sum y^2 -(\sum y)^2]}}](https://tex.z-dn.net/?f=r%3D%5Cfrac%7Bn%28%5Csum%20xy%29-%28%5Csum%20x%29%28%5Csum%20y%29%7D%7B%5Csqrt%7B%5Bn%5Csum%20x%5E2%20-%28%5Csum%20x%29%5E2%5D%5Bn%5Csum%20y%5E2%20-%28%5Csum%20y%29%5E2%5D%7D%7D)
The determination coefficient is given by 
Let's analyze one by one the possible options:
a. can never be equal to the value of the coefficient of determination (r2).
False if r = 1 then
b. is always larger than the value of the coefficient of determination (r2).
False not always if r= 1 we have that 
and we don't satisfy the condition
c. is always smaller than the value of the coefficient of determination (r2).
False again if r =1 then we have and we don't satisfy the condition
d. can be equal to the value of the coefficient of determination (r2).
True on the special case when r =1 we have that
