1. Create a number line, like the one in your Online lesson, and plot the following irrational numbers.

−1.92857143609… and −1.68547930216…

Note

Writing out the steps is not required, but they are here as a guide to the solution if more support is needed.

Step 1:

Round each irrational number to a more usable rational number.

−1.92857143609 is rounded to −1.9

−1.68547930216 is rounded to −1.7

Now both irrational numbers are represented by decimals that have values in the tenths.

Step 2:

Create a number line with a range of −2 to −1, that is divided into tenths.

Step 3:

Plot the rounded forms of the irrational numbers on the number line to represent an estimated point for each value.

Explain your thinking

2. Explain how to plot irrational numbers on a number line.

• Discuss that irrational numbers need to be rounded to a more usable number. 
• Number lines are created using the same procedures used for rational numbers. 
• Estimation is used to plot irrational numbers as close to their actual position as possible.