Answer:
d) Squared differences between actual and predicted Y values.
Step-by-step explanation:
Regression is called "least squares" regression line. The line takes the form = a + b*X where a and b are both constants. Value of Y and X is specific value of independent variable.Such formula could be used to generate values of given value X.
For example,
suppose a = 10 and b = 7. If X is 10, then predicted value for Y of 45 (from 10 + 5*7). It turns out that with any two variables X and Y. In other words, there exists one formula that will produce the best, or most accurate predictions for Y given X. Any other equation would not fit as well and would predict Y with more error. That equation is called the least squares regression equation.
It minimize the squared difference between actual and predicted value.
You could multiply the two numbers to get a product of 15.98 pounds.
Radius of 1 button = r = 3x
Fabric required to cover 1 button = Area of the circle
= 
= 
= 
Total number of buttons = x
Fabric required to cover 1 button =
Fabric required to cover x buttons = 
Hence, fabric required to cover x buttons
sq. units
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