default [x,t,theta,n] button variable help

[Joe Horn]

You are getting "A" when you press that key because your current app is Solve. The variable produced by the [x,t,theta,n] key depends on the current app. Look at the top of your screen to see which is the current app. Change to another app to use that app's default variable. For example, select the Function app to make that key type "X". Most apps yield "X". Solve yields "A". Parametric yields "T". Polar yields "Theta" (the character). Sequence yields "N".

Hope that helps!