How do you simplify square root of -10 times the root of -40?

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Answer 1 · 2015-09-10T10:12:55

$sqrt(-10) * sqrt(-40) = color(green)(20$

square root of -10 times the root of -40 can be written as :

$sqrt(-10) * sqrt(-40)$

One of the rules in Exponents says that $color(blue)(sqrta*sqrtb=sqrt(ab)$

Hence $sqrt(-10) * sqrt(-40) = sqrt(-10*-40)$

$=sqrt(400)$

$=sqrt(20*20)$

$=color(green)(20$

PS: It can also be equal to $-20$ , but $color(green)(20$ is the principal square root.