## Absolute Value

• Why should I bother learning this?
Tell them that they need to be able to answer questions using numbers that make sense in context. Ask students to compare their responses to How do I get to ______ from here? and How far is it to ______? Fill in the blank with some well-known local place that requires just a right or left turn out of the parking lot and a short (straight) drive or walk. Extend the discussion into a clear differentiation between direction and distance.

• What's so important about closed and open dots in an absolute value graph? The issue here is not really absolute value. It's the distinction between the inequality symbols <, > and , . Use time as a way to model comparisons that include a number and those that exclude it.
Today is Tuesday. You have less than a week until your exam. Could that exam be next Tuesday? E < 7 It will take at least an hour to cook tonight's dinner. Could it possibly take exactly an hour? D 60 min.

Help students to see that the symbols that have two parts (including half of an equals symbol) are the ones that include the compared number and so require a closed dot.

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