Determine equation given 3 points and 2 lines

[euro94]

Homework Statement

Two coplanar lines l1 and l2 are perpendicular to each other, l1 passes through the points (-3,2,3) and (-8,10,6). Find the equation for l2 if it passes through the point (7,49,25)

Homework Equations

The Attempt at a Solution

determine the equation of l1 and use the dot or cross product?

 

[HallsofIvy]

What you have under "The attempt at a solution" is NOT an attempt at a solution! If you think you neeed to find the equation of the line l₁, the find it! What is the equation of that line? What must the equation of any line through (7, 49, 25) look like?