Question 110141
The process is called FOIL, standing for First, Inside, Outside, Last.

4x and 3x are First.
-5 and 3x are Inside.
4x and -2 are Outside.
-5 and - 2 are Last.
:
You need to find the product of the Firsts PLUS the product of the Insides PLUS the product of the Outsides PLUS the product of the Lasts, and then combine like terms.
:
{{{4x*3x=12x^2}}}
{{{-5*3x=-15x}}}
{{{4x*-2=-8x}}}, and
{{{-5*-2=10}}}
:
Then adding them all together:
:
{{{12x^2-15x-8x+10}}}, and then collecting the two like terms:
:
{{{12x^2-23x+10}}}
:
And you are done.