The first two terms have a GCF $\displaystyle{4}{x}\usepackage{cmbright}\Huge\$ and the second two terms have a GCF 3. Factor those out.

$\displaystyle{4}{{x}}^{{2}}-{4}{x}+{3}{x}-{6}={4}{x}{\left({x}-{1}\right)}+{3}{\left({x}-{2}\right)}\usepackage{cmbright}\Huge\$

Since there is no common factor, the expression cannot be factored.