Answer Entry for CBA
A negative mixed fraction could be expressed as -3-2/3, but the student is encouraged to use -(3+2/3).
In those cases where there is more than one input required (systems of equations, for example), it sometimes happens that the student will realize that he has made an error in a previous step. In those cases, the [^] character can be entered to return (go up) to the previous input in order to make a correction.
Similarly, when a graphing problem requires more than one point, an erroneously entered point can be removed by placing the cursor directly over the point and pressing [ENTER].
If the calculator is unable to interpret the answer, as for example the reply
2X² -3X + , then the message ERR:SYNTAX will result and program execution will be terminated. This will happen, but can be remedied as described under Error Recovery. In many cases, probable syntax errors have been anticipated and have been avoided by programmed messages such as "WRONG NEGATIVE" (used negation rather than subtraction or vice versa), "WHOLE EQUATION", (neglected to input the entire equation where required), etc.
In those rare cases that extensive alphabetical characters are needed in the response, students may find it advantageous to use the [2nd] [A-LOCK] option, which temporarily locks the Alpha key.