It appears that you used the first two terms as the first factor and the last two terms as the second factor. Using FOIL:

$\displaystyle{\left({4}{{x}}^{{2}}-{4}{x}\right)}{\left({3}{x}-{6}\right)}={12}{{x}}^{{3}}-{24}{{x}}^{{2}}-{12}{{x}}^{{2}}+{24}{x}={12}{{x}}^{{3}}-{36}{{x}}^{{2}}+{24}{x}\usepackage{cmbright}\Huge\$

This product does not equal the given expression. The correct answer is: Cannot be factored.