Wzór
[tex] \sqrt{(x_2 - x_1 {)}^{2} + (y_2 - y_1 {)}^{2} } [/tex]
Obliczmy
[tex] \sqrt{(6 - 2 {)}^{2} + (1 - 8 {)}^{2} } = \\ = \sqrt{ {4}^{2} + ( - 7 {)}^{2} } = \\ = \sqrt{16 + 49} = \\ = \sqrt{65} [/tex]
