\begin{equation*}
  \begin{aligned}
    b_2^{МНК} = \dfrac{\sum\limits_{i=1}^n (p_i-\bar{p})(w_i-\bar{w})}{\sum\limits_{i=1}^n(w_i-\bar{w})^2} = \dfrac{\sum\limits_{i=1}^n([\beta_1 + \beta_2w_i+u_{pi}]-[\beta_1 + \beta_2 \bar{w} + \bar{u}_p])(w_i-\bar{w})}{\sum\limits_{i=1}^n(w_i-\bar{w})^2}\\ 
    = \dfrac{\sum\limits_{i=1}^n(\beta_2(w_i - \bar{w})(w_i - \bar{w} + (u_{pi} - \bar{u}_p)(w_i - \bar{w})}{\sum\limits_{i=1}^n(w_i-\bar{w})^2} = \beta_2 + \dfrac{\sum\limits_{i=1}^n(u_{pi}-\bar{u})(w_i - \bar{w})}{\sum\limits_{i=1}^n(w_i-\bar{w})^2}
  \end{aligned}
\end{equation*}

\begin{flushright}
  \eqno($\Upsilon$)
\end{flushright}