Mark the correct alternative in the following:

A vector parallel to the line of intersection of planes and is


The two planes are, and



The line of intersection of planes and


is parallel to







The line of intersection of planes and


is parallel to


Alternative:


The two planes are, and



or, 3x - y + z=1 and x - 4y - 2z=2


Putting, z=k, we get,


3x - y + k=1 ………………………. (1)


and x - 4y - 2k=2 …………………… (2)


Multiplying equation (2) by 3 and then subtracting equation (1) from it, we get,


3(x - 4y - 2k) - (3x - y + k)=(3×2) - 1


3x - 12y - 6k - 3x + y - k=6 - 1


- 11y - 7k=5



Substituting y, in equation (1) we get,




33x + 5 + 7k + 11k=11


18k=11 - 5 - 33x









Equation of the line of intersection,





The line of intersection of planes and


is parallel to .

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