Math
posted by Thanh on .
What is the probability that x^2+7x+k will factor if k is greater or equal to zero and less than or equal to 20, considering k is an integer.
How do I do this?

Basically, let k=1,2,...20 and try to factor all of the 20 cases. See which one factors and divide the factorable cases by 20 to get the probability.
On the other hand, we know than to factor, k must have two factors that add up to 7, such as 1*6,2*5,3*4...
I'll let you work from here.