SOLUTION: assuming the polynomial below is factorable, what is the maximum value of b? x^2+bx-20

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Question 1109256: assuming the polynomial below is factorable, what is the maximum value of b?
x^2+bx-20
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
If x%5E2%2Bbx-20 is factorable, x%5E2%2Bbx-20=%28x%2Bp%29%28x-q%29=x%5E2%2B%28p-q%29x-pq ,
Where p and q are positive integers.
So, pq=20 and b=p-q .
As p and q must be positive integer factors of 20 ,
The maximum value of b=p-q is 20-1=highlight%2819%29