When you mix a primary (in this case red) with the complimentary secondary colour (in this case green) you will get a brown or dark grey of some sort.
If you mix the colors red and green you'll get the color brown.
When you mix cadmium red and yellow you will get the sap green color.
If you mix red, green, and yellow you will get a dark green bogey color!
If you mix red and green paint you get brown.
Brown
you get the color brown
Dark red!
Dark red!
When you mix red and green you get a kind of brownish color and when you mix it with a little bit of black you make it darker.
brown
red green and blue
PURPLE