A. Addition, Subtraction, Division, Multiplication
The order of operations of these four calculations is: (1) multiplication and division, in order from left to right, and (2) addition and subtraction, in order from left to right. To change this order of operations you must use parentheses.
The TI89 does recognize implied multiplication under certain conditions.
Valid Entries


Entry

Calculator Interpretation

Invalid Entries


Entry

Calculator Interpretation

Single variable named xy  
Function call evaluated at 3  
Matrix index to element a[2,4] 