Conditional formatting by results in two different cells

[Supe]

I want my background to highlight red if the cell in column D AND the cell in
column L are both less than zero.

 

[JE McGimpsey]

One way:

Assume the cell to have the CF applied is in Row 2:

CF: Formula is =AND($D2<0,$L2<0))
Format1: <pattern>/<red>