[tex] \sqrt{72} = \sqrt{36 \times 2} = \sqrt{36} \times \sqrt{2} = 6 \times \sqrt{2} = 6 \sqrt{2} [/tex]
[tex] \sqrt{8} = \sqrt{4 \times 2} = \sqrt{4} \times \sqrt{2} = 2 \times \sqrt{2} = 2 \sqrt{2} [/tex]
[tex] \sqrt{128} = \sqrt{64 \times 2} = \sqrt{64} \times \sqrt{2} = 8 \times \sqrt{2} = 8 \sqrt{2} [/tex]
