Tap Edit
Select Clear all variables
Tap ok
Tap on the end of the equation
Enter a comma and the pronumeral
Check your equation for common errors involving:
not closing brackets
more than one decimal point in a single number
having 'to the power' twice
fractions without a numerator or denominator
Tap Zoom (in the toolbar)
Select Auto
Tap Zoom in or Zoom out to refine the window settings
Tap Zoom (in the toolbar)
Select Auto
Tap Zoom in or Zoom out to refine the window settings
Tap the settings button
(gear icon at the top left-hand corner of the screen)
Select Default Setup
Tap ok