Answer:
(a + 9)(a - 5)
Step-by-step explanation:
Given
a² + 4a - 45
Consider the factors of the constant term (- 45) which sum to give the coefficient of the a- term (+ 4)
The factors are + 9 and - 5 , since
9 × - 5 = - 45 and 9 - 5 = 4 , then
a² + 4a - 45 = (a + 9)(a - 5) ← in factored form
