To solve the quadratic equation \(x^2 + 10x + 25 = 0\) using the perfect square trinomial pattern, we can recognize that the left side is a perfect square trinomial. It can be factored as follows:
\[ (x + 5)^2 = 0 \]
To solve for \(x\), we take the square root of both sides:
\[ x + 5 = 0 \]
Now, isolate \(x\) by subtracting 5 from both sides:
\[ x = -5 \]
So, the solution to the equation \(x^2 + 10x + 25 = 0\) is:
\[ \boxed{-5} \]