Find the value of `lambda` for which the planes `2x-4y+3z=7` and `x+2y+lambdaz=18` are perpendicular to each other.

Explanation

To find the value of \( \lambda \) for which the planes \( 2x - 4y + 3z = 7 \) and \( x + 2y + \lambda z = 18 \) are perpendicular to each other, we will follow these steps:

### Step 1: Identify the normal vectors of the planes
The general equation of a plane can be expressed in the form \( Ax + By + Cz = D \), where \( (A, B, C) \) is the normal vector to the plane.

For the first plane \( 2x - 4y + 3z = 7 \):
- The normal vector \( \mathbf{n_1} = (2, -4, 3) \).

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