Answer:
(x - 1)(3x + 4)
Explanation:
Given
3x² + x - 4
Consider the factors of the product of the coefficient of the x² term and the constant term which sum to give the coefficient of the x- term.
product = 3 × - 4 = -12 and sum = + 1
The factors are - 3 and + 4
Use these factors to split the x- term
3x² - 3x + 4x - 4 ( factor the first/second and third/fourth terms )
= 3x(x - 1) + 4(x - 1) ← factor out (x - 1) from each term
= (x - 1)(3x + 4) ← in factored form