[tex] \sqrt{864} [/tex] [tex] \sqrt{4 \times 216} [/tex] [tex] \sqrt{4 \times 4 \times 54} [/tex] [tex] \sqrt{4 \times 4 \times 2 \times 27} [/tex] [tex] \sqrt{4 \times 4 \times 2 \times 9 \times 3} [/tex] now take out the pairs. [tex]4 \sqrt{2 \times 9 \times 3} [/tex] take out any of the square roots like 9 [tex]4 \times 3 \sqrt{2 \times 3} [/tex] Now put it all back together. [tex]12 \sqrt{6} [/tex] I believe that is the answer.
