To evaluate an expression, follow these steps:

• Type an expression containing any valid combination of numbers, variables and functions. Any variables or functions in this expression should be defined earlier in the worksheet.

• Press the “=” key. Mathcad computes the value of the expression and shows it after the equals sign.

Whenever you evaluate an expression, Mathcad shows a final placeholder at the end of the equation. You can use this placeholder for unit conversions, as explained in Chapter 9, “Units and Dimensions.” As soon as you click outside the region, Mathcad hides the placeholder.