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Write a Formula for a Total Cost

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Expressions using Letter-Numbers · Formulas from quantities · 3:09

You'll learn: Write a formula for total cost as price times quantity.

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Write a Formula for a Total Cost

3:09

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Write a Formula for a Total Cost

You'll learn: Write a formula for total cost as price times quantity.

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Formulas from quantities

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Express an Age Relationship with a Letter
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Write Perimeter Formulas for Regular Shapes
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Write Perimeter Formulas for Regular Shapes
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Calendar and number-grid relationships

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Write Relative Values in a Calendar or Number Grid
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Write Relative Values in a Calendar or Number Grid
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Evaluating algebraic expressions

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Substitute a Number Without Changing the Expression's Structure
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Substitute a Number Without Changing the Expression's Structure
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Why Do Adjacent Angles on a Line Add to 180°?
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Why Do Adjacent Angles on a Line Add to 180°?
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Geometric facts versus measurements

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Why Does Measuring a Diagram Not Prove a Geometric Fact?
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Why Does Measuring a Diagram Not Prove a Geometric Fact?
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Perpendicular lines

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Why Do Four Equal Intersection Angles Make Perpendicular Lines?
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Why Do Four Equal Intersection Angles Make Perpendicular Lines?
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Parallel lines and segment intersections

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When Do Segments Meet—and What Happens If We Extend Them?
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When Do Segments Meet—and What Happens If We Extend Them?
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Lines through paper folding

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Make Parallel and Perpendicular Creases by Folding
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Transversals and distinct angle measures

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