SOLUTION: Suppose f(x)=(x−2)(x+9). (a) For which values of x is the function f(x) positive? Enter your answer using inequalities. (b) For which values of x is the function f(x)

Algebra ->  Inequalities -> SOLUTION: Suppose f(x)=(x−2)(x+9). (a) For which values of x is the function f(x) positive? Enter your answer using inequalities. (b) For which values of x is the function f(x)      Log On


   



Question 901151: Suppose f(x)=(x−2)(x+9).
(a) For which values of x is the function f(x) positive? Enter your answer using inequalities.
(b) For which values of x is the function f(x) negative? Enter your answer using inequalities.

Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
The roots are the critical x values.

Check in the intervals of x, -infinity%3Cx%3C-9, -9%3Cx%3C2, and 2%3Cx%3Cinfinity.

Recognize that f(x) is a parabola with positive coefficient on x%5E2. f will be positive for x%3C-9 and for x%3E2.