If it's anything like the fx-115MS model then yes you can mix the polar and rectangular coordinates in an equation, but I think your problem may lie in that the "60" cannot be negative (since thats the magnitude/length of the vector)
I live about an hour south of Nashville and I'm hoping today's the day (at least if I pass that is), since they were mailed out Yesterday morning. But realistically I figure it'll be tomorrow. :waitwall: