Question

Find the distance between the points (1, 3) and (-7, 2).

Answer 1

$A(x_1;\ y_1);\ B(x_2;\ y_2)\\\\the\ distance\ between\ A\ and\ B:\\\\d=\sqrt{(x_2-x_1)^2+(y_2-y_1)^2}\\-------------------------\\\\A(1;\ 3);\ B(-7;\ 2)\\\\d=\sqrt{(-7-1)^2+(2-3)^2}=\sqrt{(-8)^2+(-1)^2}=\sqrt{64+1}\\\\=\boxed{\sqrt{65}}$