Find the equation of the plane through the line of intersection of the planes x – 3y + 2z – 5 = 0 and 2x – y + 3z – 1 = 0 which is perpendicular to the plane 5x + 3y – 6z + 8 = 0 ?

We know that equation of plane passing through the line of intersection of planes


(a1x + b1y + c1z + d1) + k(a2x + b2y + c2z + d2) = 0


So equation of plane passing through the line of intersection of planes


x – 3y + 2z – 5 = 0 and 2x – y + 3z – 1 = 0 is given by


(x – 3y + 2z – 5) + k(2x – y + 3z – 1) = 0


x(1 – 2k) + y( – 3 – k) + z(2 + 3k) – 5 – k = 0 …… (1)


Given that plane (1) is perpendicular if


a1a2 + b1b2 + c1c2 = 0 ……(2)


We know that two planes are perpendicular to plane,


5x + 3y + 6z + 8 = 0 ……(3)


Using (1) and (3) in equation (2),


5(1 + 2k) + 3(2 + k) + 6(3 – k) = 0


5 + 10k + 6 + 3k + 18 – 6k = 0


29 + 7k = 0


7k = – 29



Put the value of k in equation (1),


= 0




51 x + 15 y – 50 z + 173 = 0


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