Answer:
(x + 6)(x + 13)
Explanation:
Given
x² + 19x + 78
Consider the factors of the constant term (+ 78) whuch sum to give the coefficient of the x- term (+ 19)
The factors are + 6 and + 13 , since
6 ×13 = + 78 and 6 + 13 = + 19 , then
x² + 19x + 78 = (x + 6)(x + 13) ← in factored form