SOLUTION: By the regression feature of a graphing utility, identify the least squares regression line for the data points shown in the image below. https://s13.postimg.org/szphbjozb/A_GRA

Algebra ->  Graphs -> SOLUTION: By the regression feature of a graphing utility, identify the least squares regression line for the data points shown in the image below. https://s13.postimg.org/szphbjozb/A_GRA      Log On


   

Question 1050561: By the regression feature of a graphing utility, identify the least squares regression line for the data points shown in the image below.
https://s13.postimg.org/szphbjozb/A_GRAPH.png
A.) +y+=+-0.62x+%2B+0.57+
B.) +y+=+-0.98x+%2B+0.8+
C.) +y+=+-0.76x+%2B+0.7+
D.) +y+=+0.17x+%2B+1.63+
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
Step 1: Find x%2Ay and x%5E2 as it was done in the table below.
x..|..y|x%2Ay|x%5E2
-2|..3|-6..|4
-1|..1|-1..|1
1..|..2|2...|1
1..|-1|-1..|1
2..|-2|-4..|4

Step 2: Find the sum of every column:
sum%28x%29=+1
sum%28y%29=3
sum%28xy%29=-10
sum%28x%5E2%29=11

Step 3: Use the following equations to find a and b:


a=%283%2A%2811%29-1%28-10%29%29%2F%285%2A11-1%5E2%29
a=%2833%2B10%29%2F%2855-1%29
a=+43%2F54
a=0.796

b=%28n%2Asum%28xy%29-sum%28x%29%2Asum%28y%29%29%2F%28n%28sum%28x%5E2%29-sum%28x%29%5E2%29%29
b=%285%2A%28-10%29-1%2A3%29%2F%285%2A11-1%5E2%29
b=+-53%2F54
b=-0.981

Step 4: Substitute a and b in regression equation formula
y+=+a+%2B+bx
The equation of the regression line is:
y+=+0.796+%26%238722%3B+0.981x
or
y+=+-0.98x%2B+0.8
so, your answer is B.) +y+=+-0.98x+%2B+0.8+