We have the expression:( x - 2 ) / ( x + 9 ) ( x - 5 )We have to find how many values of x must be excluded. The rule is : denominator must never equal zero. Anything divided by zero is undefined.x + 9 ≠ 0, x ≠ - 9x - 5 ≠ 0, x ≠ 5.Answer: Two values must be excluded, x = - 9 and x = 5.