SOLUTION: FIND THE DOMAIN OF THE FUNCTION f(x)= 4/ square root of x - 9 "f(x) equals 4 divided by the square root of x - 9" The answer is x > 9. But I keep getting the answer- x is

Algebra ->  Rational-functions -> SOLUTION: FIND THE DOMAIN OF THE FUNCTION f(x)= 4/ square root of x - 9 "f(x) equals 4 divided by the square root of x - 9" The answer is x > 9. But I keep getting the answer- x is       Log On


   



Question 369593: FIND THE DOMAIN OF THE FUNCTION
f(x)= 4/ square root of x - 9
"f(x) equals 4 divided by the square root of x - 9"
The answer is x > 9.
But I keep getting the answer- x is greater than OR EQUAL to 9.
What am i doing wrong?? HELP PLEASE.

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
The domain of the function is all the x values for which f%28x%29 is defined.
The square root function is defined as long as the argument is not negative.
x-9%3E=0
x%3E=9
Division by zero is also undefined so the x value when the denominator equals zero is not in the domain.
x-9=0
x=9
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.
.
So both of those must hold: x must be greater than or equal to 9 and x cannot equal 9, so that leaves that x%3E9
.
.
.
Domain:x%3E9 or in interval notation, (9,infinity)
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graph%28300%2C300%2C-2%2C18%2C-10%2C10%2C0%2C4%2Fsqrt%28x-9%29%29