Answer:
(3x - 2)
Step-by-step explanation:
Given that the area A = length × width
A = 3x² + 7x - 6 ← factor to obtain length
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 × - 6 = - 18 and sum = + 7
The factors are + 9 and - 2
Use these factors to split the x- term
3x² + 9x - 2x - 6 ( factor the first/second and third/fourth terms )
= 3x(x + 3) - 2(x + 3) ← factor out (x + 3) from each term
= (x + 3)(3x - 2)
We know (x + 3) is the width , then (3x - 2) is the length