Question

question
factor completely.
$x^3 - 4x^2 - 9x + 36$

Explanation:

Step1: Group terms in pairs

$x^3 - 4x^2 - 9x + 36 = (x^3 - 4x^2) + (-9x + 36)$

Step2: Factor out GCF from each pair

$= x^2(x - 4) - 9(x - 4)$

Step3: Factor out common binomial

$= (x - 4)(x^2 - 9)$

Step4: Factor difference of squares

$= (x - 4)(x - 3)(x + 3)$

Answer:

$(x - 4)(x - 3)(x + 3)$