What is the distance between (–6, 3, 4) and (–5, –1, 1) ?

1 Answer
Dec 19, 2017

sqrt(26)

Explanation:

You may be familiar with the two-dimensional distance formula, which tells us that the distance between (x_1, y_1) and (x_2, y_2) is:

sqrt((x_2-x_1)^2+(y_2-y_1)^2)

There is a similar formula for three dimensions for the distance between (x_1, y_1, z_1) and (x_2, y_2, z_2), namely:

sqrt((x_2-x_1)^2+(y_2-y_1)^2+(z_2-z_1)^2)

So in our example, the distance between (x_1, y_1, z_1) = (-6, 3, 4) and (x_2, y_2, z_2) = (-5, -1, 1) is:

sqrt((x_2-x_1)^2+(y_2-y_1)^2+(z_2-z_1)^2)

= sqrt(((-5)-(-6))^2+((-1)-3)^2+(1-4)^2)

= sqrt(1^2+(-4)^2+(-3)^2)

= sqrt(1+16+9)

= sqrt(26)