Need show all work to multiply : ( 2 + sqrt -25 ) ( 4 - sqrt -100 )

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Step-by-step explanation:

The best thing to do here is to simplify those negative square roots.  I see that you are in imaginary or complex numbers in math right now.  

Simplifying the first negative radical, keeping in mind that i-squared = -1:

Simplifying the next negative radical:

Now we can rewrite those sets of parenthesis without the radicals!

(2 + 5i)(4 - 10i)

FOIL now:

2*4 = 8, then 2*(-10i) = -20i--> 8-20i

5i*4 = 20i, then 5i(-10i) = -50i^2

So altogether this is what we have:

You see that -20i and +20i cancel each other out, leaving us with just

Remember that -1 = i^2, so we can rewrite as:

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