How do you simplify $sqrt(400/5)$ ?

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Answer 1 · 2018-03-15T18:23:21

See below.

$sqrt(400/5) = sqrt(400)/sqrt(5)$

$sqrt(400)/sqrt(5)=20/sqrt5$

$=20/sqrt(5) * sqrt(5)/sqrt(5)$

$=(20sqrt(5))/5 = 4sqrt5$

Answer 2 · 2018-03-15T18:24:30

$sqrt(400/5)=4sqrt(5)$

$sqrt(400/5)=sqrt(400)/sqrt(5)=20/sqrt(5)$

We want to rationalize the denominator. Here we are just getting rid of the square root, shown in blue.

$20/sqrt(5)=(20color(blue)(sqrt(5)))/(sqrt(5)*color(blue)(sqrt(5)))=(20sqrt5)/5=4sqrt(5)$

How do you simplify sqrt(400/5)sqrt(400/5)?