Answer:
x = - [tex]\frac{5}{6}[/tex] , x = [tex]\frac{1}{2}[/tex]
Step-by-step explanation:
To find the zeros let f(x) = 0 , that is
12x² + 4x - 5 = 0
Consider the factors of the product of the x² term and the constant term which sum to give the coefficient of the x- term.
product = 12 × - 5 = - 60 and sum = + 4
The factors are - 6 and + 10
Use these factors to split the x- term
12x² - 6x + 10x - 5 = 0 ( factor first/second and third/fourth terms )
6x(2x - 1) + 5(2x - 1) = 0 ← factor out (2x - 1) from each term
(2x - 1)(6x + 5) = 0
Equate each factor to zero and solve for x
6x + 5 = 0 ⇒ 6x = - 5 ⇒ x = - [tex]\frac{5}{6}[/tex]
2x - 1 = 0 ⇒ 2x = 1 ⇒ x = [tex]\frac{1}{2}[/tex]
