Simplify ( square root of 5)( square root of 5)

$(\sqrt{5}) (\sqrt{5})$

Combine using the product rule for radicals.

$\sqrt{5 \cdot 5}$

Write the expression using exponents.

Multiply $5$ by $5$ .

$\sqrt{25}$

Rewrite $25$ as $5^{2}$ .

$\sqrt{5^{2}}$

Pull terms out from under the radical, assuming positive real numbers.

$5$