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| Question 118551:  Simplify the expression.
 1a) square root of 54
 1b)square root of 72
 1c) square root of 5/9
 1d) square root of 7/36
 1e) square root of 9/11
 1f)square root of 9/25
 Answer by jim_thompson5910(35256)
      (Show Source): 
You can put this solution on YOUR website! I'll do the first three to show you how to do these problems 
 1a)
 
 
  Start with the given expression 
 The goal of simplifying expressions with square roots is to factor the radicand into a product of two numbers. One of these two numbers must be a perfect square. When you take the square root of this perfect square, you will get a rational number.
 So let's list the factors of 54
 Factors:
 1, 2, 3, 6, 9, 18, 27, 54
 
 
 Notice how 9 is the largest perfect square, so lets factor 54 into 9*6
 
 
 
  Factor 54 into 9*6 
 
  Break up the square roots using the identity  
 
  Take the square root of the perfect square 9 to get 3 
 So the expression
  simplifies to   
 ----------------------------
 Check:
 Notice if we evaluate the square root of 54 with a calculator we get
 
 
   
 and if we evaluate
  we get 
 
   
 This shows that
  . So this verifies our answer 
 
 
 
 
 1b)
 
 
  Start with the given expression 
 The goal of simplifying expressions with square roots is to factor the radicand into a product of two numbers. One of these two numbers must be a perfect square. When you take the square root of this perfect square, you will get a rational number.
 So let's list the factors of 72
 Factors:
 1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 36, 72
 
 
 Notice how 36 is the largest perfect square, so lets factor 72 into 36*2
 
 
 
  Factor 72 into 36*2 
 
  Break up the square roots using the identity  
 
  Take the square root of the perfect square 36 to get 6 
 So the expression
  simplifies to   
 ----------------------------
 Check:
 Notice if we evaluate the square root of 72 with a calculator we get
 
 
   
 and if we evaluate
  we get 
 
   
 This shows that
  . So this verifies our answer 
 
 
 
 
 1c)
 
 
  Start with the given expression 
 
 
  Break up the fraction 
 
 
  Take the square root of 9 to get 3 
 
 So
  simplifies to  
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