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Question
State the two normal equations used in fitting a straight line
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Solution
The constants ‘a’ and ‘b’ are estimated by solving the following two normal Equations
`sum"Y"` = na + `"b"sum"X"` .........(2)
`sum"XY" = "a"sum"X" + "b"sum"X"^2` .........(3)
Where ‘n’ = Number of years given in the data.
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