Posted by **Scott** on Monday, July 23, 2007 at 8:25pm.

Find all positive values for k for which each of the following can be factored.

X^2-x-k

Using the quadratic equation,

x= 1/2 +-1/2* sqrt (1+4k)

Now, the sqrt has to be of a positive number, so 1+4k>0 so any value of

k>-1/4 should work.