What is the distance between (–6, 3, 4) and (4, –1, 2)?

1 Answer
Feb 23, 2016

I assume that you know the distance formula (square root of sum of corresponding coordinates squared)

Well, that formula can actually be EXTENDED to the third dimension. (This is a very powerful thing in future mathematics)

What that means is that instead of the known sqrt((a-b)^2 + (c-d)^2)

We can extend this to be sqrt((a-b)^2 + (c-d)^2 + (e-f)^2)

This problem is beginning to look a lot easier huh?

We can just plug in the corresponding values into the formula

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

sqrt((-10)^2 + (4)^2 + (2)^2)

sqrt(100 + 16 + 4)

sqrt(120)

which is equal to 2sqrt30

And we are done.