Determine the value of λ for which the following planes are perpendicular to each other.

Question

Determine the value of λ for which the following planes are perpendicular to each other. and

Philoid · Accepted Answer

Given planes, and

We know that planes and are perpendicular if

We have and

Now,

⇒(λ + 4 – 21) = 0

⇒λ = 21 – 4 = 17

Hence, for λ = 17 the given planes are perpendicular.