Simplify 3\(\sqrt{45} - 12\sqrt{5} + 16\sqrt{20}\), leaving your answer in surd form.

A.

29\(\sqrt{5}\)

B.

14\(\sqrt{15}\)

C.

12\(\sqrt{15}\)

D.

11\(\sqrt{15}\)

Correct answer is A

3 \(\sqrt{45} - 12\sqrt{5} + 16\sqrt{20}\)

= 3 x \(\sqrt{9 \times 5} - 12 \times \sqrt{5} + 16 \times \sqrt{4 \times 5}\)

= 3 x 3 x \(\sqrt{5} - 12 \times \sqrt{5} + 16 \times 2 \times \sqrt{5}\)

= 9\(\sqrt{5} - 2 \sqrt{5} + 32 \sqrt{5}\)

= 9\(\sqrt{5} + 32\sqrt{5} - 12\sqrt{5}\)

= 29\(\sqrt{5}\)