Question 153674
{{{x^2-8x-20=(x+p)(x+q)=x^2+(p+q)x+pq}}}
{{{pq=-20}}}
{{{p+q=-8}}}
Since pq is negative, either p or q must be negative.
Since p+q is negative, the larger factor is negative.
1 is not the solution, pq=160
2 is not the solution, p+q=8
3 is not the solution, pq=20
4 is the solution, pq=-20, p+q=-8

4)p=-10, q=2