SOLUTION: How do you simplify a radical of 45

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Question 604351: How do you simplify a radical of 45
Found 2 solutions by nerdybill, jim_thompson5910:
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
sqrt%2845%29
factor (using prime numbers):
sqrt%285%2A9%29
sqrt%285%2A3%2A3%29
then, for pull out "pairs":
3sqrt%285%29

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Take advantage of the fact that sqrt%28xy%29=sqrt%28x%29%2Asqrt%28y%29 and 45 = 9*5 to get...

sqrt%2845%29

sqrt%289%2A5%29

sqrt%289%29%2Asqrt%285%29

3%2Asqrt%285%29


As we can see in the last step above, taking the square root of 9 gives us 3, which is why we factored 45 into 9*5.
So sqrt%2845%29 simplifies to 3%2Asqrt%285%29