How do you simplify $- 3 \sqrt{5} \cdot \sqrt{20}$ $-3sqrt5*sqrt20$ ?

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Answer 1 · 2018-03-28T23:33:13

$- 30$ $-30$

$- 3 \sqrt{5} \cdot \sqrt{4 \cdot 5}$ $-3sqrt5*sqrt(4*5)$
$- 3 \sqrt{5} \cdot 2 \sqrt{5}$ $-3sqrt5*2sqrt5$
$- 6 \cdot 5$ $-6*5$
$- 30$ $-30$

Answer 2 · 2018-03-28T23:35:12

Combine terms in the radical to find the simplified expression is -30

We can multiply the radicals directly, since they're the same root:

$- 3 \sqrt{5} \cdot \sqrt{20} = - 3 \sqrt{5 \cdot 20}$ $-3sqrt(5)*sqrt(20)=-3sqrt(5*20)$

Once we carry out the multiplication under the radical, we can then simplify:

$\Rightarrow - 3 \sqrt{100} = - 3 \cdot 10$ $rArr -3sqrt(100)=-3*10$

$\Rightarrow - 30$ $color(red)(rArr -30)$

How do you simplify -3sqrt5*sqrt20−3√5⋅√20-3sqrt5*sqrt20?