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If you want to write the expression shown without a radical in the denominator, what should you multiply by?

$$\frac{-\sqrt{2}}{(\sqrt{2}+7)}$$

$\cfrac{(\sqrt{2}-7)}{(\sqrt{2}-7)}$

$\cfrac{(\sqrt{2}+7)}{(\sqrt{2}+7)}$

$\sqrt{2}+7$

$\sqrt{2}-7$