# Thread: vector from origin to point

1. ## vector from origin to point

i have been trying to solve this problem for 2 hours...couldn't get anywhere.

"consider 2 points located at r1 and r2, seperated by a distance r=|r1-r2|

find a vector A from origin to a point on the line between r1 and r2 at a distance xr from the point at r1, where x is some number."

i tried to find an equation for the line r and then tried to solve it with vector A...to find the intersection point...but couldn't get anywhere.

HELP!!

2. Originally Posted by silmania
"consider 2 points located at r1 and r2, seperated by a distance r=|r1-r2|
find a vector A from origin to a point on the line between r1 and r2 at a distance xr from the point at r1, where x is some number."
Use the vector defined by the given points: $\vec d = r_2 - r_1.
$

Then the equation you want is $r_1+x\vec d$