Answer:
C
Explanation:
given
3x² + 18x + 24 ← factor out 3 from each term
= 3(x² + 6x + 8) ← factorise the quadratic
Consider the factors of the constant term (+ 8) , whichsum to give the coefficient of the x- term (+ 6)
the factors are + 2 and + 4 , since
+2 × + 4 = + 8 and + 2 + 4 = + 6
use these factors to solit the x- term
x² + 2x + 4x + 8 ( factor the first/second and third/fourth terms )
= x(x + 2) + 4(x + 2) ← factor out (x + 2) from each term
= (x + 2)(x + 4)
Thus the factored form is
3x² + 18x + 24
= 3(x + 2)(x + 4)
with (x + 4) being a factor