Answer
(x+3)(x-12)
Work Step by Step
$x^{2}$ - 9x -36
step 1. Enter x as the first term of each factor
$x^{2}$ - 9x - 36= (x__)(x _)
Step 2. To find the second term of each factor, we must find two integers whose product is -36 and whose sum is -9
List pairs of factors of the constant, -36
(1,-36)(-1,36)(-2,18)(2,-18)(3,-12)(-3,12)(4,-9)(-4,9)(6,-6)
step 3. The correct factorization of $x^{2}$ - 9x - 36 is the one in which the sum of the Outside and Inside products is equal to -9x.
So (3,-12) satisfy the condition
$x^{2}$ -9x -36 = $x^{2}$ +3x -12x - 36= (x+3)(x-12)
