To solve the quadratic equation \( x^2 - 16x + 64 = 0 \) using the perfect square trinomial pattern, we can rewrite the left side of the equation.
The expression \( x^2 - 16x + 64 \) is a perfect square trinomial. It can be factored as:
\[ (x - 8)^2 = 0 \]
Next, we set the factored equation equal to zero:
\[ (x - 8)^2 = 0 \]
Taking the square root of both sides gives us:
\[ x - 8 = 0 \]
Solving for \( x \):
\[ x = 8 \]
So, the solution to the equation \( x^2 - 16x + 64 = 0 \) is:
\[ \boxed{8} \]