What is the Projection of Line M_1P on Plane \pi?

[chmate]

Homework Statement

Given \pi: \begin{cases}l_1: \frac{x-2}{4}\ = \frac{y-1}{2}\ = \frac{z+5}{-4} &\\l_2: \frac{x+4}{-2}\ = \frac{y+1}{0}\ = \frac{z}{1} & \end{cases} and the point M=(1,2,3) outside the plane. Find the projection of the line M_1P on plane \pi where P is the intersection point of lines l_1, l_2.2. The attempt at a solution

All I can do is that I can find the equation of plane \pi but don't have any idea what to do next. So I need your help.

Thank you.

 

[Quinzio]

How can you use the plane normal vector ?
Just make some "expriment" with a pen on your desk as a plane.

 

[vela]

What is M_1? You never defined what it is.

Start by finding P.