Answer:
x = - 3, x = 5
Step-by-step explanation:
To find the zeros equate the expression to zero
3x² - 6x - 45 = 0 ( divide through by 3 )
x² - 2x - 15 = 0
Consider the factors of the constant term (- 15) which sum to give the coefficient of the x- term (- 2)
The factors are - 5 and + 3 , since
- 5 × + 3 = - 15 and - 5 + 3 = - 2 , then
(x - 5)(x + 3) = 0 ← in factored form
Equate each factor to zero and solve for x
x + 3 = 0 ⇒ x = - 3
x - 5 = 0 ⇒ x = 5
