Answer
(x + 5)(x - 1)
Work Step by Step
To factor the trinomial, you find two factors of the third term that sum to the coefficient of the second term. In this case we are looking for two factors of -5 that add to 4. These factors are 5 and -1, so each of these become the second term in two different binomials with x as the first term, leading to (x + 5)(x - 1).
