Question

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Answer 1

http://openstudy.com/study#/updates/4f8719fde4b0505bf086b304

Answer 2

\[72=36\times 2\] so
\[\sqrt{72}=\sqrt{36}\times \sqrt{2}=6\sqrt{2}\]

Answer 3

factor 72 with highest possible perfect square

example

18 = 9 x 2 (9 is a perfect square)

Answer 4

also
\[\sqrt{x^2}=x\] assuming\(x\geq 0\)