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Question
The equations of the two lines of regression are 2x + 3y − 6 = 0 and 5x + 7y − 12 = 0. Identify the regression lines
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Solution
Let 2x + 3y − 6 = 0 be the regression equation of Y on X
∴ The equation becomes 3Y = −2X + 6
i.e., Y = `(-2)/3 "X" + 2`
Comparing it with Y = bYX X + a, we get
bYX = `(-2)/3`
Now, the other equation 5x + 7y − 12 = 0 is the regression equation of X on Y.
∴ The equation becomes 5X = − 7Y + 12
i.e., X = `(-7)/5 "Y" + 12/5`
Comparing it with X = bXY Y+ a', we get
bxy = `(-7)/5`
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