Find the values of `k` for which the equation `x^2+5k x+16=0` has no real roots.

Explanation

To find the values of \( k \) for which the quadratic equation \( x^2 + 5kx + 16 = 0 \) has no real roots, we will analyze the discriminant of the quadratic equation.

### Step-by-Step Solution:

1. **Identify the coefficients**:
The given quadratic equation is \( x^2 + 5kx + 16 = 0 \). Here, we can identify the coefficients as follows:
- \( a = 1 \)
- \( b = 5k \)
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