Question

Find the values of x for which $x^2-4x-32$ is negative:

Answer 1

Given that,

$x^2-4x-32$

$\Rightarrow x^2-(8-4)x-32$

$\Rightarrow x^2-8x+4x-32$

$\Rightarrow x(x-8)+4(x-8)$

$\Rightarrow (x-8)(x+4)$

Hence, $-4<x<8$

This is the answer.