SOLUTION: I am having a hard time with my math today. I have a problem that I am close to answering but I cannot figure out the last part. Could someone help me finish this up please? multip
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Question 464581: I am having a hard time with my math today. I have a problem that I am close to answering but I cannot figure out the last part. Could someone help me finish this up please? multiply. (sqrt6+2sqrt5)(sqrt6-2sqrt5). I have (sqrt(6)^2-2sqrt30+2sqrt30)-(2sqrt5)^2=sqrt(6)^2-(2sqrt5)^2=6-??? I cannot figure out the (2sqrt5)^2. Helllp!!! Answer by lwsshak3(11628) (Show Source):
You can put this solution on YOUR website! (sqrt6+2sqrt5)(sqrt6-2sqrt5)
You should recognize that these are factors of a difference of two squares:
ie, (a+b)(a-b)=a^2-b^2
in given case, a=√6 and b=2√5
so, (√6+2√5)(√6-2√5)=(√6)^2-(2√5)^2=6-4(5)=6-20=-14
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