#1**+2 **

Distance formula:

https://www.screencast.com/t/2b4GDp2N

Hope this helps! : )

Supergirl
May 9, 2017

#2**+3 **

I could just tell you....but I want to explain it, so that you don't have to just memorize it!

Say we want to know the distance between these two points:** ****(1, 2)** and** (4, 6)**

The length of the purple line is the distance between them.

Hey! We can make a right triangle out of this, with the purple line as the hypotenuse. Now we can use the Pythagorean theorem to find the length of the purple line, which I called c.

3^{2} + 4^{2} = c^{2}

25 = c^{2}

5 = c

And the distance formula comes from the Pythagorean theorem.

(difference in x's)^{2} + (difference in y's)^{2} = (distance between the two points)^{2}

\(\sqrt{(x_1-x_2)^2+(y_1-y_2)^2}=\text{distance between the two points}\)

And that is the distance formula!

Here's a better explanation: https://www.youtube.com/watch?v=nyZuite17Pc

hectictar
May 9, 2017