Question

What is the factorization of the trinomial below?

4x^2+28x + 48
O A. 4(x+3)(x+4)
O B. 4(x+2)(x+4)
O C. (x+2)(x+16)
O D. (x+3)(x + 4)

Answer 1

A

Explanation:

Given

4x² + 28x + 48 ← factor out 4 from each term

= 4(x² + 7x + 12)

To factor the quadratic

Consider the factors of the constant term (+ 12) which sum to give the coefficient of the x- term

The factors are + 4 and + 3, since

4 × 3 = 12 and 4 + 3 = 7, thus

x² + 7x + 12 = (x + 3)(x + 4) and

4x² + 28x + 48 = 4(x + 3)(x + 4) → A

Answer 2

`4x^2+28x + 48=\\4(x^2+7x+12)=\\4(x^2+3x+4x+12)=\\4(x(x+3)+4(x+3))=\\4(x+3)(x+4)`