Answer:
(2a + 1)(2a - 5)
Step-by-step explanation:
Given
4a² - 8a - 5
Consider the factors of the product of the coefficient of the a² term and the constant term which sum to give the coefficient of the a- term
product = 4 × - 5 = - 20 and sum = - 8
The factors are + 2 and - 10
Use these factors to split the a- term
4a² + 2a - 10a - 5 ( factor the first/second and third/fourth terms )
= 2a(2a + 1) - 5(2a + 1) ← factor out (2a + 1) from each term
= (2a + 1)(2a - 5)
