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A regression has $X^\top X = \begin{pmatrix}2 & 1\\ 1 & 2\end{pmatrix}$ and $X^\top y = \begin{pmatrix}4\\ 5\end{pmatrix}$ . What is the second OLS coefficient?

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A regression has X⊤X=(2112)X^\top X = \begin{pmatrix}2 & 1\\ 1 & 2\end{pmatrix}X⊤X=(21​12​) and X⊤y=(45)X^\top y = \begin{pmatrix}4\\ 5\end{pmatrix}X⊤y=(45​). What is the second OLS coefficient?

More regression and econometrics questions

A regression has $X^\top X = \begin{pmatrix}2 & 1\\ 1 & 2\end{pmatrix}$ and $X^\top y = \begin{pmatrix}4\\ 5\end{pmatrix}$ . What is the second OLS coefficient?