Problem: Color cellrow(s) with column A less than 50 and column B = 0

Solution:

Example sheet

Instructions:

1. Select the whole area you want to use "conditional formatting" on
2. Go to tab "Home"
3. Click "Conditional formatting"
4. Click "New rule..."
5. Click "Use a formula to determine which cells to format"
6. In "Format values where this formula is true" type =AND($A1<50,$B1=0)
7. Click "Format" button
8. Click "Fill" tab
9. Choose a color
10. Click ok!
11. Click ok!
12. Click ok!