If the scalar projection of vector `xhati-hatj+hatk1` on vector `2hati-hatj+5hatk is 1/sqrt30`. The find the value of x.

Explanation

To solve the problem, we need to find the value of \( x \) given that the scalar projection of the vector \( \mathbf{A} = x \hat{i} - \hat{j} + \hat{k} \) onto the vector \( \mathbf{B} = 2 \hat{i} - \hat{j} + 5 \hat{k} \) is \( \frac{1}{\sqrt{30}} \).

### Step 1: Identify the vectors
We have:
- \( \mathbf{A} = x \hat{i} - \hat{j} + \hat{k} \)
- \( \mathbf{B} = 2 \hat{i} - \hat{j} + 5 \hat{k} \)

### Step 2: Calculate the magnitude of vector \( \mathbf{B} \)
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