SOLUTION: How to work out (-5-√-100)^2 Answer -75+100i How to get the answer without calculator

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Question 360436: How to work out (-5-√-100)^2
Answer -75+100i
How to get the answer without calculator
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
(-5-√-100)^2
FOIL
(-5-√-100)*(-5-√-100) = 25+%2B+5sqrt%28-100%29+%2B+5sqrt%28-100%29+%2B+%28-100%29
which is
25+%2B+10sqrt%28-100%29+-+100%29 = -75+%2B+10i%2Asqrt%28100%29 = -75 + 10i*10 = -75 + 100i