Sorry, but is that just the direction vector of the line of intersection?
If so, then do I need to make it into the form r = \underline{a} + \lambda \underline{c} ?
The only way I know of making that form is by doing the dot product of the plane and its normal which doesn't help as the normal is what I'm trying to find :confused:
Homework Statement
Two planes r_1 and r_2 have the equations:
r_1 = ( 1 - \lambda ) \underline{i} + ( 2 \lambda + \mu ) \underline{j} + ( \mu - 1 ) \underline{k}
r_2 = ( s - t ) \underline{i} + ( 2s - 3 ) \underline{j} + ( t ) \underline{k}
If a point lies in both r_1 and r_2 then...