Last number from the sample test!

Question

A plane P passes by the coordinates:
A(1,0,-7); B(-2,-1,0); C(0,0,-3)

Using the equation of the line D:

x= 7+12t, y= -1-6t, z= 2-2t,

Find the equation of a line that's entirely part of the plane P and that is perpendicular to the line D at point Q(1,2,3)

Thank you