SOLUTION: The range of f(x) = 5x2 + 25x − 55 is y > or equal to -345/4. Determine the values of x in the domain of f for which f(x) = 15. (Enter your answers as a comma-separated l

Algebra ->  Functions -> SOLUTION: The range of f(x) = 5x2 + 25x − 55 is y > or equal to -345/4. Determine the values of x in the domain of f for which f(x) = 15. (Enter your answers as a comma-separated l      Log On


   

Question 623723: The range of f(x) = 5x2 + 25x − 55 is y > or equal to -345/4.

Determine the values of x in the domain of f for which f(x) = 15. (Enter your answers as a comma-separated list.)

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,  ·

f(x)=5x^2 + 25x-55    | parabola opening Upward 5>0 with min at x = -2.5

f(-2.5) = -345/4   Yes!  y ≥  -86.25

 f(x) = 15 is an horizontal line, domain can be any real number