Answer:
(x + 7)(2x + 3)
Explanation:
Given
2x² + 17x + 21
Consider the factors of the product of the x² term and the constant which sum to give the coefficient of the x- term.
product = 2 × 21 = 42 and sum = + 17
The factors are + 14 and + 3
Use these factors to split the x- term
2x² + 14x + 3x + 21 ( factor the first/second and third/fourth terms )
= 2x(x + 7) + 3(x + 7) ← factor out (x + 7) from each term
= (x + 7)(2x + 3) ← in factored form