1.) 12x^4yz^2 + 18xy - 24xz2.) 6x^2 - 9x - 4x + 63.) 20x^2 + 25x + 4x + 5

From the problem, we have :
[tex]12x^4yz^2+18xy-24xz[/tex]The common factor will be 6x, this will be :
[tex]\begin{gathered} 6x(2x^3yz^2)+6x(3y)-6x(4z) \\ \text{Factor out 6x} \\ 6x(2x^3yz^2+3y-4z) \end{gathered}[/tex]The answer is :
[tex]6x(2x^3yz^2+3y-4z)[/tex]