SOLUTION: I have a problem with another like the first, but this makes no sense to me ata all. The section says use the rule a√b*c√d=ac√bd. Using this the problem is: 10

Algebra ->  Square-cubic-other-roots -> SOLUTION: I have a problem with another like the first, but this makes no sense to me ata all. The section says use the rule a√b*c√d=ac√bd. Using this the problem is: 10      Log On


   



Question 588027: I have a problem with another like the first, but this makes no sense to me ata all. The section says use the rule a√b*c√d=ac√bd. Using this the problem is:
10√8*3√10= ?
I tried several times using this rule above and I got the answer 30√80
to show how I came to that conclusion, I broke it down a step at a time as follows: (10*3)√(8*10)= 30√80, however the book tells me the answer is 120√5. How do I get the answer they are showing, or is my answer actually correct. I am confused. Plase help, THANK YOU!

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
I have a problem with another like the first, but this makes no sense to me ata all. The section says use the rule a√b*c√d=ac√bd. Using this the problem is:
10√8*3√10= ?
I tried several times using this rule above and I got the answer 30√80
to show how I came to that conclusion, I broke it down a step at a time as follows: (10*3)√(8*10)= 30√80, however the book tells me the answer is 120√5.
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30%2Asqrt%2880%29+=+30%2Asqrt%2816%2A5%29+=+30%2Asqrt%2816%29%2Asqrt%285%29
= 30%2A4%2Asqrt%285%29
= 120sqrt%285%29