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You can also use this palette to assign constraints to dimensions. See Constraining Dimensions.

Mathematical Calculations

To perform a calculation, enter the values in the top field of the palette, using parentheses as needed to create inner expressions. No spaces are allowed. The four mathematical operators should be entered as +, -, * (multiply), and / (divide).

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Include the values and press Enter to get the result.
 

Defining and Using Variables

In addition to calculating numerical equations, you can use the Calculator Palette to define variables. Subsequent values and variables can then be based on variables you've already created.
In the calculator field, enter the variable definition in the format "variable name=value" (in this example, Length=5). The value can be a number, function, or another variable. Variables are case sensitive and cannot have spaces. 

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 Press Enter, and the new variable appears, with its calculated value.
 

Using Expressions in Data Field

Numbers or variables from the Calculator Palette can be used as values in the Inspector Bar or Coordinate fields.
As an example, define Length and Width variables, and draw a rectangle (see Rectangle). Select the first corner point, but not the second point. 

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For subsequent fields of the Inspector Bar or Coordinate Fields, do not press Tab to scroll. Instead, place the cursor in the desired field, then press F2 to access the Calculator Palette.