# What is the speed of an object that travels from ( -1, 7,2)  to ( -3, -1,0 )  over 2 s?

Jan 1, 2016

$4.24 \text{units/s}$

#### Explanation:

The distance between the 2 points is given by:

d=sqrt((-1+3)^2+(7+1)^2+(2-0)^2

$\therefore d = \sqrt{{2}^{2} + {8}^{2} + {2}^{2}}$

$d = \sqrt{72} = 8.48 \text{units}$

$\therefore v = \frac{d}{t} = \frac{8.48}{2} = 4.24 \text{units/s}$