1. **State the problem:** Find the x-coordinates where the graphs of \( f(x) = \cos^2(x) + 6\cos(x) \) and \( g(x) = -5 \) intersect for \( 0 \leq x < 2\pi \).
2. **Set the functions equal to find intersection points:**
$$ \cos^2(x) + 6\cos(x) = -5 $$
3. **Rewrite the equation:**
$$ \cos^2(x) + 6\cos(x) + 5 = 0 $$
4. **Use substitution:** Let \( y = \cos(x) \), then the equation becomes:
$$ y^2 + 6y + 5 = 0 $$
5. **Factor the quadratic:**
$$ (y + 5)(y + 1) = 0 $$
6. **Solve for \( y \):**
$$ y = -5 \quad \text{or} \quad y = -1 $$
7. **Check domain of cosine:** Since \( \cos(x) \) ranges from -1 to 1, \( y = -5 \) is invalid.
8. **Solve for \( x \) when \( \cos(x) = -1 \):**
On \( [0, 2\pi) \), \( \cos(x) = -1 \) at:
$$ x = \pi $$
9. **Final answer:** The x-coordinate of the intersection point is:
$$ \boxed{\pi} $$
Cosine Intersection 7D82Af
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