The Number Line
2. Subtracting Natural Numbers

a. SCALE: Set the scale of the number line that is:
• Type in a number >=1 and <=500.
• Then click on the Set Scale button.  

   

Remember: arrow for first number starts from 0, arrow for second number starts from end of first arrow.

•Now click on Ready for First Number.

   

b. FIRST NUMBER: Click and drag the point on the red slider to the value of the first number.

This is a positive number and it is the first number so the red arrow moves to the right starting from 0 (zero).

•Now click on Ready for Second Number.

   

c. Second Number: Click and drag the point on the blue slider to the value of the second number.

This is a positive number - but we are subtracting so the blue arrow moves to the left starting from the end of the red arrow.

d. DIFFERENCE: What is the difference?
• Click on "Show Difference " to see it on the number line.

   

e. EQUATION: Write down the equation for the subtraction.
• Click on Show Equation to check your answer.

   

•Click on Reset to start over.

   

                    

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     LFS with idea for number line by Megan Yanes and for pseudo-slider by Zen Biker Maniac - Created with GeoGebra