For what value of x is the rational expression below equal to zero? x-9/(x-4) (x+4)

The value of x is 9

Step-by-step explanation:

* It first we must to talk about the rational expression

- The rational expression is defined for all values of x except

  the values make the denominator = zero

Ex: If the rational expression is a/b, then b ≠ 0 to be defined

* In any rational expression we must to avoid any values

 make denominator = zero

* If we want to make rational expression equal to zero then we

  must put the numerator equal to zero

* Now lets look to our problem

∵ The rational expression (x - 9)/(x - 4)(x + 4)

- To make this rational expression equal to zero, we must

  equate the numerator by zero

∴ x - 9 = 0 ⇒ add 9 to both sides

∴ x = 9

* The value of x is 9

* Remember ⇒ x must not equal to 4 or -4 to avoid make

  this rational expression undefined

ab will be equal to