b=n∑xiyi−∑xi∑yin∑xi2−(∑xi)2b=\frac{n\sum{x_iy_i}-\sum{x_i}\sum{y_i}}{n\sum{x_i^2}-(\sum{x_i})^2} b=n∑xi2−(∑xi)2n∑xiyi−∑xi∑yi
a=y‾−bx‾a=\overline{y}-b\overline{x} a=y−bx
r=∑r=1nxiyi−nx‾y‾(sumr=1nxi2−nx‾2)(∑r=1nyi2−ny‾2)r=\frac{\sum_{r=1}^nx_iy_i-n\overline{x}\overline{y}}{\sqrt{(\\sum_{r=1}^nx_i^2-n\overline{x}^2)(\sum_{r=1}^ny_i^2-n\overline{y}^2)}}r=(sumr=1nxi2−nx2)(∑r=1nyi2−ny2)∑r=1nxiyi−nxy