The Least-Squares Line Thm.4.1(Least-Squares Line).Suppose that {(xk,y=1are N points, where the abscissas1are distinct.The coefficients of the least- squares line y=Ax+B are the solution to the following linear system, known as the normal equations: 位4+位-2 位+阳-2 The line y=fx)=Ax+B is the line that minimizes the root-mean-square error E2(f). The Least-Squares Line ◼ Thm. 4.1(Least-Squares Line). Suppose that {(𝑥𝑘, 𝑦𝑘)}𝑘=1 𝑁 are N points, where the abscissas {xk}𝑘=1 𝑁 are distinct. The coefficients of the least￾squares line y=Ax+B are the solution to the following linear system, known as the normal equations: ◼ The line y=f(x)=Ax+B is the line that minimizes the root-mean-square error E2 (f ). 2 1 1 1 1 1 N N N k k k k k k k N N k k k k x A x B x y x A NB y = = = = =     + =           + =         