what is the solution for this problem?

Answer:  The vertical asymptoms are " x =  3"  and " x = -3 " .
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The answer is:  " x = ± 3 " . 
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Explanation:
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The "denominator" cannot equal "0" ; since one cannot "divide by "0" ; 

So;  set the "denominator" equal to "0" ; 
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→  "  x² − 9 = 0 " ;  Solve for all values of "x" ; 

Add "9" to each side of the equation: 

→    x² − 9 + 9 = 0 + 9 ; 

to get: 

→   x²  = 9 ; 

Take the square root of each side of the equation; 
  to isolate "x" on one side of the equation; & to solve for "x" ; 

→  √(x²)  = √9 ; 

→  |x|  = 3 ; 

→  x = ± 3 .
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Answer:  The vertical asymptoms are " x =  3"  and " x = -3 " .
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The answer is:  " x = ± 3 " . 
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