Find the equation of the plane passing through a point and a vector orthogonal I have come across this question that I need a tip for.

Find the equation (general form) of the plane passing through the point $P(3,1,6)$ that is orthogonal to the vector $v=(1,7,-2)$.

I would be able to do this if it said "parallel to the vector"
I would set the equation up as
$(x,y,x) = (3,1,6) + t(1,7,-2)$
and go from there.
I don't get where I can get an orthogonal vector. Normally when I am finding an orthogonal vector I have two other vectors and do the cross product to find it.
I am thinking somehow I have to get three points on the plane, but I'm not sure how to go about doing that.
Any pointers?
thanks in advance.

vector equation of a plane is in the form : r.n=a.n,
in this case, a=(3,1,6), n=(1,7,-2).
Therefore,
 r.(1,7,-2)=(3,1,6).(1,7,-2)
           r.(1,7,-2)=(3x1)+(1x7)+(6x-2)
          r.(1,7,-2)=3+7-12
          r.(1,7,-2)=-2
   OR

r=(x,y,z)
therefore, 
(x,y,z).(1,7,-2)=-2
      x+7y-2z=-2

