Question

Find the distance between the two points in simplest radical form. (7,−1) and (9,−9)

Answer 1

The formula of a distance between two points:

`d=√((x_2-x_1)^2+(y_2-y_1)^2)`

We have the points (7, -1) and (9, -9). Substitute:

`d=√((9-7)^2+(-9-(-1))^2)=√(2^2+(-8)^2)=√(4+64)=√(68)\\\\=\qrt{4\cdot17}=\sqrt4\cdot√(17)=\boxed{2√(17)}`