(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Find the equation of the line through the point (-5,-4,2) that intersects the line at r = (7,-13,8) +t(1,2,-2) at 90 degrees.

2. Relevant equations

I guess that using the dot product for the direction vector of the line needed, (x,y,z) , with the direction of the given line will = 0. Then i get lost as to what I should be doing afterwards, in incorporating the point given with the variables that result from the dot product.

3. The attempt at a solution

So i did (x,y,z) dot (1,2,-2) to get x +2y -2z = 0

at this point, i'm not sure where to do.

Btw, the answer is r = (-5,-4,2) +t(14,-5,2).

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Equation of a line through a point and another line at 90 degrees.

**Physics Forums | Science Articles, Homework Help, Discussion**