Working with PTC Mathcad Prime > Worksheets and Regions > To Format Math Font
  
To Format Math Font
1. In a worksheet, select one or more math regions. To apply your formatting to all math regions in the worksheet, click outside a region.
2. On the Math Formatting tab, click an option in the Math Font group.
3. To restore all math formatting options of the selected regions to the predefined default settings, on the Math Formatting tab, in the Math Font group, click the Clear Format button.