The Answer Editor for mathematical expressions consists of two parts: a rectangular field into which mathematical expressions are entered (the "entry field") is to the left, and a "keypad" made of buttons with mathematical symbols is to the right (Fig. 4.1). These buttons have labels in the Tutorial, but not afterwards. Mathematical expressions are entered and edited using the buttons of the Answer Editor keypad, as well as the basic keyboard, the Left and Right arrow keys, the Tab, Enter, and Backspace keys, and the mouse.

NOTE. Buttons are displayed to correspond with the kind of problem being solved. The selection is made in such a way as to avoid giving away the correct answer. Keyboard shortcuts (Fig. 4.2) work only when the corresponding button is displayed.

Expression	Answer Editor keypad button	Keyboard equivalent
Square Root	√	(none)
Fraction	[] ⁄ []	⁄
Mixed Number	[] [] ⁄ []	(none)
Repeating Decimal	‾	(none)
Absolute Value	[] | [] |	(none)
List of Expressions	[], [], …	,
Exponent	[][]	^ (before exponent)
Multiplication Expression	[] × []	×
Percentage	%	%
Greater-Than	[] > []	>
Less-Than	[] < []	<
Greater-Than-or-Equal-To	[] ≥ []	(none)
Less-Than-or-Equal-To	[] ≤ []	(none)
Equal-To	[] = []	=
Not-Equal-To	≠	(none)
AND	AND	(none)
OR	OR	(none)

Figure 4.2: Mathematical Expressions Produced by the Answer Editor

Key	Effect
Right arrow - Tab - Enter	moves the cursor one place to the right (ahead)
Left arrow	moves the cursor one place to the left (back)
Backspace	deletes input immediately preceding (to the left of) the cursor and moves the cursor one place to the left (back) OR deletes selected input

Figure 4.3: Using Special Keys in the Answer Editor

Basic Input

When a new page is opened and contains a problem whose solution is a mathematical expression, the entry field initially contains at least one blue box. Each blue box represents a mathematical expression that forms part of the complete answer. To enter a mathematical expression one must first click on a blue box. When this is done, the cursor (or "caret") appears inside the box. The cursor marks the point at which something is entered. Material can be entered using the basic keyboard or the buttons of the keypad. Individual digits can be entered only from the keyboard. Symbols can be entered using the buttons of the keypad and, sometimes, from the keyboard as well (Fig. 4.2).

Basic Editing Tools

The cursor, showing the point at which material is entered, can be moved using the Left and Right arrows and the Tab and Enter keys. It can also be positioned using the mouse. Input can be deleted using the Backspace key (Fig. 4.3).

Selecting Input

It is possible to select a continuous portion of input by dragging the pointer with the mouse button held down. A segment that has been selected by dragging in this way can be deleted by pressing Backspace, replaced by typing, or replaced by clicking the buttons of the Answer Editor keypad. It can also be inserted into a mathematical expression such as a fraction or a square root (the selected portion is placed in the numerator position or under the square root sign, respectively).

Clear and Undo

After material has been entered, the field can be returned to its empty state by clicking on "Clear." Clicking on "Undo" cancels the most recent action. Clicking on "Undo" a second time restores the effect of the canceled action (including a "Clear" command).