Respuesta :

Answer:

The expression is undefined when x=3 or -3

Solution:

  • An expression is undefined when it's divided by 0.
  • In order to make the denominator equal 0, we need to subtract 9-9.
  • Notice that x is squared.
  • So x times itself should equal 9. What number is it?
  • That's right, 3.
  • So we have
  • 9-(3)^2=9-9=0
  • There's also another solution: x=-3 (-3•(-3)=9

Hope it helps.

Do comment if you have any query.

Hemo4

Answer: The expression is undefined when x is 3 or -3

Step-by-step explanation:

The denominator of a fraction can never be 0 because you cannot divide by 0. So all we have to do is determine the value of x when the denominator is equal to 0.

[tex]9-x^{2} =0\\[/tex]

We want [tex]x^2[/tex] to be positive so divide everything by -1

[tex]9-x^{2} =0\\\\\frac{9-x^{2}}{-1}=\frac{0}{-1} \\-9+x^2=0\\x^2-9=0[/tex]

Use difference of two squares (DOTS) to factor

[tex]x^2+9=0\\(x+3)(x-3)=0[/tex]

So x cannot be 3 or -3