i know that if line equation is given by the following
`r={a1*x+b*y+c1*z+d=0 and a2*x+b2*y+c2*z+d2=0`}
then directional vector is given by the cross product of this two plane or it is determinant of the following form
i j k a1 b1 c1 a2 b2 c2
i was trying to determine directional vecotor of r which is determined by the following form
r={y=2;3x-(3)^(1/2)*z=0}
but my result did not match to solution in source,there directional vector is determined like this r={x=3^(1/2)*lambda
(i can't write lambda directly from my keyboard),y=2;and z=3*(lambda)
and U_r={3^(1/2),0,3)
please help me(U_r is a directional vector)