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Rationalize \(\frac{5\sqrt{7} - 7\sqrt{5}}{\sqrt{7} - \sq...

Rationalize \(\frac{5\sqrt{7} - 7\sqrt{5}}{\sqrt{7} - \sqrt{5}}\)

A.

-2\(\sqrt{35}\)

B.

4\(\sqrt{7}\) - 6\(\sqrt{5}\)

C.

-\(\sqrt{35}\)

D.

4\(\sqrt{7}\) - 8\(\sqrt{5}\)

E.

\(\sqrt{35}\)

Correct answer is C

\(\frac{5\sqrt{7} - 7\sqrt{5}}{\sqrt{7} - \sqrt{5}}\) = \(\frac{5\sqrt{7} - 7\sqrt{5}}{\sqrt{7} - \sqrt{5}}\) x \(\frac{\sqrt{7} + \sqrt{5}}{\sqrt{7} + \sqrt{5}}\)

= \(\frac{(5 \times 7) + (5 \sqrt{7} \times 5) - (7 \times \sqrt{5} \times 7) (-7 \times 5)}{(\sqrt{7})^2}\)

= \(\frac{5 \sqrt{35} - 7\sqrt{35}}{2}\)

= \(\frac{-2\sqrt{35}}{2}\)

= - \(\sqrt{35}\)