How do you simplify $sqrt 7 - 2sqrt63$ ?

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Answer 1 · 2016-04-11T09:03:05

$-5sqrt7$

Recall that: $sqrt(mn)=sqrtm*sqrtn$

Using this rule, we can rewrite your problem as:

$sqrt7-2*sqrt(9*7)$

Simplifying this further by taking the $sqrt9$ outside, we get:

$sqrt7-2*3sqrt(7)$
$=sqrt7-6*sqrt(7)$

If we consider $sqrtn$ to equal $1*sqrtn$ we can further simplify the equation:

$sqrt7-6sqrt(7)$
$=1*sqrt7-6*sqrt(7)$

Therefore:

$(1-6)*sqrt7$

Completely simplified:

$=-5sqrt7$

How do you simplify sqrt 7 - 2sqrt63sqrt 7 - 2sqrt63?