SOLUTION: Find the minimum value of the function f(x) = x2 + 9x – 16. ANSWER CHOICES: –36.250 –2.500 There is no minimum<--- MY ANSWER Cannot be determined

Algebra ->  Finance -> SOLUTION: Find the minimum value of the function f(x) = x2 + 9x – 16. ANSWER CHOICES: –36.250 –2.500 There is no minimum<--- MY ANSWER Cannot be determined      Log On


   

Question 985066: Find the minimum value of the function f(x) = x2 + 9x – 16.
ANSWER CHOICES:
–36.250
–2.500
There is no minimum<--- MY ANSWER
Cannot be determined
Found 2 solutions by Alan3354, srinivas.g:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Find the minimum value of the function f(x) = x^2 + 9x – 16
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The min is the vertex, at x = -b/2a
x = -9/2 = -4.5
f(-4.5) = 20.25 - 40.5 - 16
min = -36.25

Answer by srinivas.g(540) About Me  (Show Source):
You can put this solution on YOUR website!
f(x)=x%5E2%2B9x-16
differentiate with respect to x
f'(x)=2x+9
differentiate again with x
f"(x)=2>0
so f(x) has minimum value
f(x) will be minimum when f'(x)=0
2x+9=0
x=-4.5
minimum value = f(-4.5)
= +%28-4.5%29%5E2%2B9%28-4.5%29-16
=20.25-40.5-16
= -36.250
Answer:-36.250