(Solved): beta_1 hat= {\sum_i x_i(Y_i-Y hat)}/{\sum_i x_i(x_i-x hat)} show that beta_1 hat is a linear estimat ...

beta_1 hat= {\sum_i x_i(Y_i-Y hat)}/{\sum_i x_i(x_i-x hat)} show that beta_1 hat is a linear estimator i.e it can be written in the form beta_1 hat = \sum_{i=1}^{n}\alpha_i Y_i