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You can use arithmetic expression in C.a.R. to

- set coordinates of points,

- lengths of segments,

- radii of circles,

- and sizes of angles.

Furthermore, you can display values of expressions in constructions.
Use the expression tool to place expressions on the screen (and the
right mouse button to move them). You need to enter a valid expression
into the dialog. Expressions may have an explaining text, and may or
may not display their computed value. They are moved like any other
object with the right mouse button. The explain text may contain
**LaTeX** code.

Hidden expressions are useful to compute values, and use these values later in the construction.

The value of an expression can be set with a **slider**. The user will
then be able to set the expression by moving the dot to the right or
left. A slider has a minimal and a maximal value it can reach.

Moreover, the value of an expression can be set with a **checkbox**.
The expression can then take the values 0 or 1 only. This can be used
with if(...) in other expressions.

Related topics: Angles, Circles, Object Properties, Reorder points, Syntax for Expressions

Next topic: Syntax for Expressions