Identify the value of c, and find the sum of its factors.
- 18 and 18
Practice makes perfect
We want to find the possible k-values so that the given expression can be factored using integers.
x^2+kx-19
⇕
x^2+kx+( - 19)
In this trinomial, c= - 19. Since c is negative and there is no restriction for the value of k, we need to find two factors with opposite signs and a product of - 19. Let's list the factors of - 19 and find their sum.
c|c
Factors & Sum of
of - 19 & Factors [0.4em] [-0.6em]
- 19, 1 & - 18
- 1, 19 & 18
When k is either - 18 or 18, the expression can be factored.
