Answer:
x = - 2 or x = 5
Step-by-step explanation:
Given
3x² - 9x - 30 = 0 ← in standard form
Divide all terms by 3
x² - 3x - 10 = 0
To factor the quadratic
Consider the factors of the constant term (- 10) which sum to give the coefficient of the x- term (- 3)
The factors are - 5 and + 2, since
- 5 × 2 = - 10 and - 5 + 2 = - 3, thus
x² - 3x - 10 = 0
(x - 5)(x + 2) = 0
Equate each factor to zero and solve for x
x - 5 = 0 ⇒ x = 5
x + 2 = 0 ⇒ x = - 2
