Find the angle between the two planes `2x + y-2z = 5`and `3x- 6y-2z = 7`using vector method.

Explanation

To find the angle between the two planes given by the equations \(2x + y - 2z = 5\) and \(3x - 6y - 2z = 7\) using the vector method, we can follow these steps:

### Step 1: Identify the normal vectors of the planes
The normal vector of a plane given by the equation \(Ax + By + Cz = D\) is represented by the coefficients \(A\), \(B\), and \(C\).

For the first plane \(2x + y - 2z = 5\):
- The normal vector \( \mathbf{n_1} = \langle 2, 1, -2 \rangle \)

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