Find the equation of the plane which contains the line of intersection of the planes
and
. And which is perpendicular to the plane
.
The equation of any plane through the line of intersection of the planes
and
is given by -
⇒ ![]()
So, the equation of any plane through the line of intersection of the given planes is
⇒ ![]()
⇒ ![]()
∴
…(1)
Since this plane is perpendicular to the plane
![]()
![]()
![]()
…(2)
So, the normal vector of the plane (1) will be perpendicular to the normal vector of plane (2).
Direction ratios of Normal of plane (1) = (a1, b1, c1)
≡ [(1 - 2λ), (2 - λ), (3 + λ)]
Direction ratios of Normal of plane (2) = (a2, b2, c2)
≡ (-5, -3,6)
Since the two lines are perpendicular,
a1a2 + b1b2 + c1c2 = 0
⇒ (1 - 2λ) × (-5) + (2 - λ) × (-3) + (3 + λ) × 6 = 0
⇒ -5 + 10λ - 6 + 3λ + 18 + 6λ = 0
⇒ 19λ + 7 = 0
∴ λ = -7/19
Putting the value of λ in (1), we get -
⇒ ![]()

⇒ 
⇒ ![]()
Hence, the equation of the required plane is ![]()