Simplify.

To simplify \(\sqrt{450}\), we start by factoring \(450\) into its prime factors.

First, we can divide \(450\) by \(2\):
\[
450 \div 2 = 225
\]
So, we have:
\[
450 = 2 \times 225
\]

Next, we can factor \(225\):
\[
225 \div 15 = 15
\]
or
\[
225 = 15 \times 15 = 15^2
\]
We can further factor \(15\):
\[
15 = 3 \times 5
\]
Thus, we have:
\[
225 = 3^2 \times 5^2
\]
Combining all these factors, we have:
\[
450 = 2 \times 3^2 \times 5^2
\]

Now we can rewrite the square root:
\[
\sqrt{450} = \sqrt{2 \times 3^2 \times 5^2}
\]

We can apply the property of square roots that allows us to separate the perfect squares:
\[
\sqrt{450} = \sqrt{2} \times \sqrt{3^2} \times \sqrt{5^2}
\]
Since \(\sqrt{3^2} = 3\) and \(\sqrt{5^2} = 5\), this simplifies to:
\[
\sqrt{450} = \sqrt{2} \times 3 \times 5
\]

Now multiplying \(3\) and \(5\):
\[
3 \times 5 = 15
\]
Thus, we have:
\[
\sqrt{450} = 15\sqrt{2}
\]

Therefore, the simplified form is:
\[
\boxed{15\sqrt{2}}
\]