Working with PTC Mathcad Prime > Working with Math Expressions > Entering Math Expressions > To Define a Variable
  
To Define a Variable
1. In a worksheet, type the name of the variable that you want to define.
2. Type a colon to insert the definition operator, :=.
3. In the placeholder, type a number, a string, an expression or enter one of the range operators.
Additional Information
When you define a variable, you can use it in all computations that you enter below or to the right of the equation that defines it. You can also redefine the variable and the new definition will be used in following equations.
When you enter a range operator, new placeholders appear. You must enter scalars in each of these placeholders to create a range variable.
You can evaluate variables by typing the evaluation operator immediately after their definition. For example:
You can use a matrix or vector for defining several variables at once: each element on the right side is assigned simultaneously to the corresponding element on the left side. For example: