Using "Mathulator" to Address "Absolute Value"

Absolute value can be thought of as "how much" or "distance from zero", while the "direction" is determined by whether the integer is positive or negative.  Since -3 is three spaces away from zero, |-3| (read as "the absolute value of three") is 3.  How do you find the absolute value of expressions? How is -(-3) different from -|-3|, or are they the same?

URL:

http://mathulator.com/eureka.aspx?tabindex=2&tabid=7&mod=Ac1AbsValue

The Mathulator is an online tool that can help students understand the concept by explaining sample problems and by evaluating whether statements are true or false.  The graphing component is simple to use and can plot single functions or overlay them on previous functions.

Where does this best fit?

X	Introduction	X	Direct Instruction, Exploration, Investigation
X	Reinforcement	X	Assessment
X	Intervention or Review	X	Extension

Estimated Time:

Cost, if any:	Required Equipment:	Required Plug-ins:
The Absolute Value is one of 30 free units on the Mathulator site. For access to all topics, the prepaid service costs $1.89/wk, $12.48 for 3 months, or $6.98 month to month.	A computer with Internet connection.	none

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