SOLUTION: Two numbers add to 9. What is the largest possible value for their product? A. 9/2 B. 81/4 C. 20 D. 18 E. None of these.

Algebra ->  Customizable Word Problem Solvers  -> Numbers -> SOLUTION: Two numbers add to 9. What is the largest possible value for their product? A. 9/2 B. 81/4 C. 20 D. 18 E. None of these.      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 286806: Two numbers add to 9. What is the largest possible value for their product?
A. 9/2 B. 81/4 C. 20 D. 18 E. None of these.
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
B 81/4
----------
n*(9-n) = p
-n%5E2+%2B+9n+=+p
The vertex is the local max.
It's on the line of symmetry n = -b/2a = -9/-2
n = 9/2
--> 81/4